# Questions Asked onSeptember 13, 2015

1. ## mathematics

find orthogonal trajectory of family of circles x^2+y^2+2fy+1=0.

2. ## Maths urgent

One regular polygon has twice as many sides as another. If the ratio of the interior angles of the first to that of second is 5:4, find the number of sides in each polygon?

3. ## Calculus

How can I show that the function F (x)= the integral from 2x to 5x of 1/ t dt is constant on the interval (0, +∞).

4. ## chemistry

For the decomposition of gaseous dinitrogen pentoxide (shownbelow), 2 N2O5(g).....> 4NO2(g) + O2(g) the rate constant is k = 2.8 10-3 s-1 at 60°C. The initial concentration of N2O5 is 1.52 mol/L. (a) What is [N2O5] after 5.00 min? _____mol/L (b) What

5. ## Physics

A certain aircraft has a liftoff speed of 126 km/h. (a) What minimum constant acceleration does the aircraft require if it is to be airborne after a takeoff run of 244 m? m/s2 (b) How long does it take the aircraft to become airborne? s

6. ## math

how can you find what each mark represents on a number line?

7. ## Psychology

A researcher has conducted an experiment in which she has given participants a placebo, 10mg, and 20mg of a drug. She then measured their anxiety, blood pressure, and heart rate in response to the drug. How many levels does this experiment’s independent

8. ## psychology

Dr. Jefferson is conducting an experiment in which she is interested in the effects of caffeine on visuospatial ability in adult participants. She conducts an experiment in which she gives one group a pill containing 20mg of caffeine and a second group a

9. ## Math

A nutritional formula calls for 500 g of dextrose in a total volume of 2000 ml. how many milliliters of a 70% w/v dextrose injection are needed to provide the required amount of dextrose? This seems to be a dimensional analysis problem. We have:

10. ## Physics

The driver pushes the accelerator pedal as far down as possible. The car does not accelerate above a certain maximum speed. Explain the reason for this in terms of the forces acting on the car.

11. ## Science

Which are reasons to get a claim peer reviewed? Check all that apply. A peer review verifies conclusions. A peer review proves everyone else wrong. A peer review maintains standards of the field. A peer review identifies sources of errors. A peer review

12. ## phyics

Consulting the graph shown in (Figure 1) , determine the object's average velocity over the time interval from 2 to 4 seconds. Express your answer in meters per second to the nearest integer. Position versus time graph for an object traveling with a

13. ## Math: Geometric Progression

Three numbers are in G.P. whose sum is 70. if the extremes be each multiplied by 4 and the means by 5, they will be in AP. find the numbers .

14. ## calculus

A rock is thrown upward with a speed of 48 feet per second from the edge of a cliff 400 feet above the ground. What is the speed of the rock when it hits the ground? Use acceleration due to gravity as –32 feet per second squared and approximate your

15. ## Chemistry

Calculate the number of moles of carbon atoms present in 2.2 g of ethanol (C2H6O). For this question, I would just need to find the molar mass of carbon, right? Not the molar mass of all of ethanol? So it would just be 2.2 g/ 24.02 g/mol which would equal

16. ## Physics

A 0.0500 kg ice cube at -30.0◦C is placed in 0.400 kg of 35.0◦C water in a very well insulated container. What is the final temperature? (Note: how can you check if all the ice melts at equilibrium temperature?)

17. ## Math

The temperature at noon is 75 degreesF. The temperature drops 3 degrees every half hour. What is the temperature at 4.pm. I'm studying Multiplying Rational numbers and I don't know how to set this up.

18. ## Physics

You are asked to consult for the city's research hospital, where a group of doctors is investigating the bombardment of cancer tumors with high-energy ions. The ions are fired directly toward the center of the tumor at speeds of 5.6 ×106m/s. To cover the

19. ## Math

-1/2 divided _____________= -7/3 how do I get the number that equals -7/3

20. ## Physics 111

A boat is crossing a river. The velocity of the boat relative to the water is 4.0 m/s directed perpendicular to the river's current. The velocity of the current relative to the shore is 2.0 m/s. How long will it take for the boat to cross the river?

21. ## math/science

The total surface area of Earth is about 1.97 × 10^8 square miles. The surface area of land on Earth is about 5.73 × 10^7 square miles. Find the ratio of surface area of land to that of the entire planet.

22. ## math

if a ladder 15 meters long is placed so as to reach the bottom of a window 10 meters high, what distance on the ground does the ladder adjusted if it is placed on the top of a two meter square window and what is the new angle of elevation of the top of the

23. ## Algebra

A is the amount of caffeine left in your body after two hours, C is the amount of caffeine originally ingested, and k is the half-life of caffeine (about 5.7 hours). Round all other numbers to the thousandths place. Formula A=C (0.5)2/k c=29 and k = 5.7 I

24. ## mathematics

R70000 is invested for five years.calculate a compound interest rate that would double the investment

25. ## Physics

Ball A is kicked at 40° above the horizontal. Ball B is kicked with the same horizontal component of velocity but at 55°. The speed of A is ( >or< ) the speed of B. The time A is in the air is ( >or< ) the time B is in the air. The range of A is ( >or< )

26. ## algebra

9 balls in a hat. balls are numbered 1-9. you choose 3 balls. how many possible combinations are there?

27. ## Statistics/probability

You are considering two mutual funds for your investment. The possible returns for the funds are dependent on the state of the economy and are given in the accompanying table. State of the Economy Fund A Fund B Good 20% 40% Fair 10% 20% Poor -10% -40% You

28. ## History

"The renewable energies roadmap unveiled earlier this month by the Commission sets a target of 20% for the share of total energy supply to come from renewable sources. “It is not the first time that targets for renewable energy have been fixed. In 1997,

29. ## history

The Wilmot Proviso called for popular sovereignty on the slave question in the territories won from Mexico. True False The Wilmot Proviso ____________________. passed the House and Senate. enraged the South. brought the North and South together on the

30. ## phsyics

A kicked football leaves the ground at an angle with a velocity of 20.0 m/s as shown in the figure. Suppose the kick is attempted 36.0 m from the goalposts, whose crossbar is 3.05 m above the ground. angle 37

31. ## government

Are state governments unicameral or bicameral?

32. ## Chemistry

Determine the energy and n(i) for the spectral line at 121.6 nm (orange). Hint: R(H)=2.18x10^-18 J, c=3.0x10^8, and 1x10^9 nm - 1 m. Line, nm 121.6 E, J ___ n(f) 1 n(i) ___

33. ## Physics

6) A school bus moves at 2.2 m/s as it pulls away from the bus stop what is the speed of the bus 20 s later after its speed has increased by 5.225 m/s? 7) The height of a computer screen is 31.25 cm and its width is 47 cm. a) is the area of the screen

34. ## Math (Trigonometry)

Zola can see the top of 180m cell phone at an angle of elevation of 32 degrees, and Naeem can see it an angle of elevation of 50 degrees. How far apart are Zola and Naeem if they are on a straight line with the tower? There are two possibilities.

35. ## biology

circle all the things from the list that would be included in a community. Explain why you circled those items. deer ticks mushrooms rotting leaves lady bug 3 inches of rainfall oak tree soil 75 degrees celsius kudzu 6 hours of daylight

36. ## physics

a ball tossed up at a rate of 8.7 ms/ and catches the ball at the same place on the way down. How long was the ball in the air?

37. ## Chemistry (Check)

Q: Name the group that has a general electron configuration of ns^2 and provide an example of an atom with this general configuration. A: Alkaline Earth Metals and Beryllium [He] 2s^2 Q: Name the group that has a general electron configuration of ns^2np^6

38. ## Chemistry (Check)

Q: Identify all that is incorrect about the set of four quantum numbers and explain why. {-3, 2, 1, 1/2} A. -3 because there can't be a negative orbital. Q: Identify all that is incorrect about the set of four quantum numbers and explain why. { 3, 2, 1/2,

39. ## Chemistry (Check)

Q: Number of unpaired electrons in the nitrogen atom. A: 1s^2 2s^2 2p^6. 3 unpaired electrons in the p orbital Q: Number of 4d orbitals. A: 10 Q: Maximum number of electrons that can have n=3 and l=1. A: 1s^2 2s^2 2p^6 3s^2 3p^6. 2 electrons

40. ## Chemistry

Can I know the molarity of acid rain?

41. ## statistics

what does this mean i have to do this in a spreadsheet Descriptive stats for each numeric variable

42. ## Muziwesizwe High School. Life orientation

Three practical measures to deal with water pollution that causes ill-health on a personal level

43. ## kwasa high school

Illustrate three ways on how this issues can impact negatively to the health of the people in our community or school by water pollution

44. ## Sicience

Calculate the density of a liquid that has a mass of 20g and a volume of 315.4ml

45. ## Physics

A 0.0500 kg ice cube at -30.0◦C is placed in 0.400 kg of 35.0◦C water in a very well insulated container. What is the final temperature? (Note: how can you check if all the ice melts at equilibrium temperature?)

46. ## Computer Science Principles

I need to know what's wrong with my code and it's supposed to be in the Next-Line blocking style. import java.util.Scanner; public class AreaOfCircle{public static void main(String[] args) { double PI = 3.14159;double get_this; double v; Scanner keyboard =

47. ## government

why does a nation's economic status affect its attainment of democracy?

48. ## Physics

If a ball is thrown at an initial speed of 8.0m/s at an angle of 35 degrees above the ground, what is the speed of the ball when it returns to its original height?

Is your work place an example of a primary or secondary group?

50. ## english

What does frivolity mean in this sentence After a year of serious work, Mr. David's grade 8 class enjoyed the frivolity of a party.

51. ## physics

A tennis player serves a tennis ball it is moving horizontally when it leaves the racquet. When the ball travels a horizontal distance of 12 meters, it has dropped 55cm from its original height when it left the racquet. What is the initial speed of the

52. ## college physics

You step onto a hot beach with your bare feet. A nerve impulse, generated in your foot, travels through your nervous system at an average speed of 124 m/s. How much time does it take for the impulse, which travels a distance of 1.60 m, to reach your brain?

53. ## Life Science

How are the three parts of a nucleotide attached to one another?

54. ## physics

The data in the following table describe the initial and final positions of a moving car. The elapsed time for each of the three pairs of positions listed in the table is 0.52 s. Review the concept of average velocity in Section 2.2 and then determine the

55. ## Physics

A rocket accelerates from rest at 17 m/s2 for 11 s. How far will it cover during this time? Answer in units of m. How do I solve this? do I multiply 17m/s2 by 11 seconds??

56. ## physics

A tennis player serves a tennis ball it is moving horizontally when it leaves the racquet. When the ball travels a horizontal distance of 12 meters, it has dropped 55cm from its original height when it left the racquet. What is the initial speed of the

57. ## physics

One afternoon, a couple walks three-fourths of the way around a circular lake, the radius of which is 2.12 km. They start at the west side of the lake and head due south to begin with. (a) What is the distance they travel? (b) What is the magnitude of the

58. ## Physics

A brick is dropped out of a window. It hits the ground 3.64 seconds later. How high is the window?

59. ## Physics

You throw a ball with a mass of 160 g into the air with an initial speed of 19.8 m/s. How high does the ball rise?

60. ## math

what does scale mean

61. ## chemistry

Le Chatelier's principle lab

62. ## math

how much cesium-137 would remain after 120.0 years if you started with 34.0 grams

64. ## Neuroscience

I'm struggling with the following question: The opening of chloride selective channels by a neurotransmitter X will drive membrane potential toward the chloride equilibrium potential. Assume that early during cell development, Cl is pumped into the cell

65. ## Physics

A hockey player is standing on his skates on a frozen pond when an opposing player, moving with a uniform speed of 2.0 m/s, skates by with the puck. After 1.00 s, the first player makes up his mind to chase his opponent. If he accelerates uniformly at 0.20

67. ## Geology

Look up and review these terms and what a graphical representation or formula would look like fro the relationships to: rate of change

68. ## Pregnancy

I am having a hard time understanding my directions. Below are two times lines that represent prenatal development and pregnancy. On the prenatal development time line, indicate the timing(in weeks)of the three stages of prenatal development and the major

69. ## BSu Probability

In a multiple choice examination there are 20 question, each question has four alternative answer following it and a student must select one correct answer. Four marks are given for the correct answer and one mark is deducted for every wrong answer. A

71. ## physics

What was the angle at which the car left the road if it hit a house at the apex of its flight and traveled 50 feet horizontally and 20 feet vertically?

72. ## Math

If a - 1/a = 2 then show that ( a + 1/a )^2 = 8

73. ## Geology

rate of change

74. ## PHYSICS

A metal ball tied to the end of a string 1.8 m long is whirled in a horizontal circle at 4 m/s. What is the mass of the ball if the tension on the string is 30 N?

75. ## PHYSICS

An object weighs 480 N on earth. What would its weight be on a planet whose mass is twice the mass and ratio of the earth?

76. ## PHYSICS

the gravitational force between two masses is 500 N. What is the gravitational force if the masses are doubled and distance between them is likewise doubled?

77. ## Multimedia

Not sure if you will get this right away.. but here is the question... Prompt the user for their name and then prompt the user for a number between 1 and 12. After getting the input, you will display the user’s name and then display the number with the

78. ## Chemistry

a 7.83g sample of hydrocyanic acid contains 0.290g and 4.06g of nitrogen. Find the mass of carbonin a sample of HCN with a mass of 3.37g.

79. ## Physics

The gravitational force between two masses is 500N. What is the gravitational force if the masses are doubled and distance between them is likewise doubled? What formula/s should I use?

80. ## Chemistry

a 7.83g sample of hydrocyanic acid contains 0.290g and 4.06g of nitrogen. Find the mass of carbonin a sample of HCN with a mass of 3.37g.

81. ## Physics

A metal ball tied to the end of a string 1.8 m long is whirled in a horizontal circle at 4 m/s. What is the mass of the ball if the tension on the string is 30 N? What formula/s should I use?

82. ## physics

A person travels by car from one city to another. She drives for 21.8 min at 67.1 km/h, 13.1 min at 84.6 km/h, 51.4 min at 33.5 km/h, and spends 11.5 min along the way eating lunch and buying gas. Determine the distance between the cities along this route.

83. ## chemistory

Please can some one help me balance this oxidation reaction. Mn4^- + C2O4 ^- => MnO2 + CO3 ^2-

84. ## math

the ratio of gas to ethanol is 17 to 3, how much ethanol is in 600 gallons of mixture

85. ## Physics

An ice sled powered by a rocket engine starts from rest on a large frozen lake and accelerates at +15.0 m/s2. At tl = 2.8 s the rocket engine is shut down and the sled moves with constant velocity v. At the 7800 m mark, the sled begins to accelerate at -7

86. ## math

A rectangular cake measuring 120 cm by 72 cm is to be divided into square pieces of the same size and the largest size possible.What will be the measure of the side of each square and how many pieces will there be?

87. ## Physics

A 2500-kg car is traveling at 20 m/s around a road curve of radius 200 m. Find the central force acting on the car?

88. ## algeb

help please :) 1.) 3 years ago, Vin’s age is 3 times the age of Paul. At the present, Vin’s age is twice the age of Paul. What would be their age 3 years from now if the sum of their present age is 18? 2.) Willie bought a jacket for 26.86 pesos. The

89. ## chem

The half-life of the Nobelium isotope No^257 is about 23 seconds. 644 seconds (or 28 half-life periods) after the isotope was released there were 20 grams remaining. The number of grans of No^257 after h half life periods is M= 20 * (1/2)^h where h = 0

90. ## math help

-1 3/4 3/4 < > = I think it's B

91. ## Burayu sec&prep High school

Measurement of Direction and Bearing

92. ## L.o

What ar three practical measures to deal with this environmental issue that causes ill-health on a personal level?

93. ## Math

A plane flys 230 km due north. The wind is blowing west at 85 km. what direction is the plane flying. Calculate the actual speed of the plane. What is the hearing from North?

94. ## College english

some hallucinogens can be found in plants. mescaline comes from a cactus called peyote. And certain mushroom, also known as magic mushrooms, are hallucinogens.But many hallucinogens are chemicals that don't occur in nature. some examples are: LSD,MDA,

95. ## English for Academic purposes

What are the main reasons for a wave of discontent

96. ## permutation & Combination

How many ways can you set up a committee of 4 people from 10 people?

97. ## probability

How many ways are there to roll out a 3 question True or False?

98. ## 4th grade math word problem

tim is 27 years older than tom. the sum of their ages is 337. how old is ti,?

99. ## math

a bank loaned out 60000, part of it at the rate 14% per year and the rest at a rate of 8% per year. if the interest received was 6780, how much was loaned at 14%?

100. ## Socials

What are the political views of a tenant farmer in the 1820's

101. ## math

1.) 3 years ago, Vin’s age is 3 times the age of Paul. At the present, Vin’s age is twice the age of Paul. What would be their age 3 years from now if the sum of their present age is 18? 2.) Willie bought a jacket for 26.86 pesos. The jacket’s price

Brianna is organizing a group of staff from her engineering company to provide Saturday afternoon tutoring for students at the nearby middle school. In order for her group of staff to remain stable, what is the optimal number of people she should recruit

103. ## LIVINGSTONIA UNIVERSITY

A STONE IS DROPPED DOWN A PIT AND HITS THE BOTTOM 4.5 SECONDS LATER.CALCULATE THE DEPTH OF THE PIT.

104. ## Charlestown high school

L.o List and discuss any four factors that could threaten the core functions of the media

105. ## Chemistry

In the reaction, PCl3 + Cl2 ------> PCl5 the concentration of the reactants at equilibrium were each determined to be 7.2 mol/L, and the product at 0.050 mol/L. Calculate the equilibrium constant (rounding to 2 significant figures and using scientific

106. ## english

Point out the pronoun Sentence : I had watched the movie on TV

107. ## Difficult algebriac word problem

I have some bananas on sunday,on monday morning i ate some of them and at night it became double,on tuesday morning i ate same number of bananas and at night also it became double,this process continued till saturday and all the bananas were finished.find

108. ## Intermediate math

I have to factor these two problems but am having some difficulties X^3y^6-64 & (x+y)^3+(x-y)^3

109. ## Tholulwazi

Physical sciences A car is stationary at first. It moves off with an acceleration of 2 m.s power -2. Calculate how fast it will be moving after 10 seconds.

110. ## Science (Physics)

(3.2534x10^4m)+(7.25x10^6m)/(4.26442x10^-3km)-(7.1299x10^-5km)

111. ## Sokisi high school

What can we do about poverty ?

112. ## Math- Algebra

A 600 meters long train travels through a 4200 meter tunnel. Two full minutes elapsed from time the front of the train enters the tunnel until the last wagon exits the tunnel. What is the speed, in meters per second, of the train?

113. ## Maths

You have 400 meters of fencing to use to make a rectangular enclosure. Give a detailed explanation of the different dimensions and areas that you are able to create using the set amount of fencing that you have. You may also show the dimensions of the

114. ## grammar

The word _______ always takes a singular verb, regardless of what follows it there who it that

115. ## College Algebra

how do you find the sloution of each of the following rational euations ?? ▶ 4 / m+2 - 2 / m-3 = 6 /(m+2)(m-3) ▶ 3x-2 / 5x+5 = 4x-3 / 6x+7

116. ## Chemistry

The equation for lowering the freezing point of a solvent is given in your manual. Given that the freezing point for the pure solvent is 79.4 °C , the molality is 0.1 m , and the freezing point depression constant is 6.9 °C/m , determine the freezing

118. ## Maths

Factorise as far as possible: 1) 2a^2b + 8a^2b^2 The answer i got for this is 2ab(a+4ab). I'm not entirely sure if this is fully factorised or not. Can you please correct me if i am wrong. 2) x^2 + 5x - 6 I'm not sure how i can do this. Can someone please

119. ## Pre-calculus- URGENT

Convert the rectangular coordinate (-8,i (square root of 3) into polar coordinates. How do I do this?? I tried every way I knew of to convert the y coordinate (i (square root of three)) to polar form, but it didn't work. I think that the polar form of the

120. ## math/science

If 0 is t when the year is 1982, what would be the value of t in 1990? How many years is that? From 1982 to 1992 the cost of the manufacturing a PC has decreased by about the same percentage each year. The cost, C (in dollars), in year t can be modeled by

121. ## physics

Vector Upper A Overscript right-arrow EndScripts has a magnitude of 75 units and points due west, while vector Upper B Overscript right-arrow EndScripts has the same magnitude and points due south. Find the magnitude and direction of (a) Upper A Overscript

122. ## math

If there are two farmers who have grown grass in the circular field then what should be length of rope so that equal crop is distributed to both if rope is tied at the center of the circular field if r is radius of the circle

123. ## math - age problem

3 years ago, Vin’s age is 3 times the age of Paul. At the present, Vin’s age is twice the age of Paul. What would be their age 3 years from now if the sum of their present age is 18?

124. ## Math

If a - 1/a = 2 then show that ( a + 1/a )^2 = 8

125. ## Math

When the tap is turned on, a sink will fill at a uniform rate in 60 seconds. If the plug is removed, the sink will empty at a uniform rate in 80 seconds. How long will it take to fill the empty sink with the tap on and plug removed?

126. ## vocabulary

I need the word stratify in a sentence for a 7th grader

127. ## Physics

how are the fundamental laws and principles of physics related to the complexity that we see in nature? 2) How do the laws of physics apply to other sciences such ad biology, chemistry, and earth science? Give a specific example to show the connection - is

128. ## maths

How many different rectangles with integral measurements can be drawn with perimeter as 32

129. ## Math

At present, the sum of the ages of a father and his son is 33 years. Determine the smallest number of years until the father's age is 4 times the son's age.

130. ## math

Greg is at his house.He gets in his car and drives north 9.6 miles and stops at the store.Then he turns around and drives south 8.4 miles to go to his friend's house.How far is the friend's house from Greg's house?

131. ## math

1.4 divided by 36.96

132. ## Physics

On the question that someone posted.....I asked my teacher on what formula I should use and said I should use this one: V^2= Vo^2+2ax (V^2 is the velocit, Vo is the initial velocity, a is accerlation and x distance . An automobile is traveling at 30 km/hr.

133. ## Maths

Rearrange in the form ax+by+c=0 1) y=-2x/7 - 6 2) y+4 = 3/5(x-1) Please help Thankyou 😘

134. ## algebra

A boy can row 18km. downstream and return a distance of 16 km/hr upstream in 5hrs. If the rate of the current is 6km/hr, What is the boy's rate of rowing in still water?

135. ## grammar

How children's drawings develop (1. is, are) a fascinating subject. For example, a two-year-old and sometimes even a three-year-old (2. does not, do not) create any recognizable forms when scribbling, and most of the children recently studied by a child

136. ## english

african slaughter rituals should be allowed in the suburbs

137. ## MATH

GIVE ME AN EXAMPLE OF A MULTI-STEP NUMBER SENTENCE THAT INCLUDES EXPONENTS (THAT WOULD INVOLVE ORDER OF OPERATIONS AND INCLUDE AT LEAST THREE NUMBERS).

138. ## Algebra II

line passing through (0,3) that is perpendicular to x + y = 5 I thought it was y = -2x + 3 Answer is: y = x + 3 How did they get this? Thank you so much

139. ## chemistry

The rate constant of a reaction is 6.2 x 10^-3s-1 at 25 degrees C, and the activation energy is 33.6 KJ/mol.. What is k at 75 degrees C? Enter your answer in scientific notation.

140. ## Chemistry

Determine the Energy and n(i) for the spectral line at 121.6 nm (orange). Given: spectral line: 121.6 nm n(f) = 1 Find Energy and n(i)

141. ## Chemistry (Check)

The Lyman series. Of the four lines, 91.2nm, 97.2nm, 102.6 nm, and 121.6nm, which one has the A. Highest wavelength? _____ B. Highest energy? ______ C. Highest frequency?_(1)____ which equals__(2)____ My answers A. 91.2 B. 121.6 C. (1) 121.6 C. (2) energy

142. ## math

A recipe good for 4 servings requires 1/8 tsp. of black pepper and 1/2 tsp/ of salt. how much pepper and how much salt needed for 2 servings?

143. ## algebra

A boy can row 18km. downstream and return a distance of 16 km. upstream in 5hrs. If the rate of the current is 6km/hr, What is the boy's rate of rowing in still water?

144. ## Physics

If each point charge has a value of -q for its charge, and the radius of the balloon is R, what is the magnitude of the NET Electric Field, E, at the location of each point charges, due to the other five? Your answer may only be in terms of q, R, π, k,

145. ## Physics

If six points charges are distributed on a balloon encased within a cube,in such a manner that the points charges appear like dots on a die and if each point charge has a value of -q for its charge, and the radius of the balloon is R, what is the magnitude