Harry

Popular questions and responses by Harry
1. Physics

A race driver has made a pit stop to refuel. After refueling, he leaves the pit area with an acceleration whose magnitude is 6.0m/s 2 . After 4.0s he enters the main speedway. At the same instant, another car on the speedway and traveling at a constant

2. Calculus

Given the table below for selected values of f(x), use 6 right rectangles to estimate the value of the integral from 1 to 10 of f(x)dx. Table: 1 3 4 6 7 9 10 4 8 6 10 10 12 16 The only problem I'm having with this is figuring out the values of f(2.5),

3. AP chemistry

Liquid butane, C4H10, is stored in cylinders, to be used as a fuel. The normal boiling point of butane is listed as -0.5 C. (a) suppose the tank is standing in the sun and reaches a temperature of 35 C. Would you expect the pressure in the tank to be

4. Maths

A runner has four different pairs of shoes. If two shoes are selected at random, what is the probability that they will be a matching pair? Answer: 1/7 Thanks for any help

5. physics

What displacement must be added to a 50cm displacement in the +x-direction to give a resultant displacement of 85cm at 25 degrees

6. Math

3 quarters of a sum of money is 21p. What is the sum of money.

7. Ap chem

Why does pf3 have dipole dipole internolecular forces? I thought it had dispersion...

8. Phi103

Reporter: A new campaign finance reform bill being considered by Congress would limit the amount of campaign contributions that political candidates can receive. However, a survey of candidates running for mayor, governor, and senate seats shows that not

9. statistics

A company has four production sections viz., S1, S2, S3 and S4 which contribute 30%, 20%, 28% and 22% of the total output. It was observed that those sections respectively produced 1%, 2%, 3% and 4% defective units. If a unit is selected at random and

10. Spanish

Need help with FOUR Spanish questions @snra Escribe este verbo en el pasado: Hoy yo voy a la escuela. Ayer yo _______ a la escuela My Answer: fui Escribe este verbo en el pasado: Cada domingo, yo doy un paseo. Cada domingo, yo __________ un paseo. My

11. Math

Please Check My Answer: Find the probability that you throw a dart and land in the region labeled "G" Here is a link to the image: I can't place it in here, but if you google the question, the very first image that pops up (A square with different colors

12. Math

Construct an isosceles triangle PQR in which PQ = PR, base QR = 5.6 centimetres, angle PQR = 75 degrees using a ruler and a pair of compasses. Draw its lines/line of symmetry.

13. math

semir, sarah and sung so decided to raise money for a local homeless shelter by working in a local deli. the deli agreed to donate to the shelter a portion of the profits from each meal the three sold. semir sold 3 times as many meals as sarah. sung sold 2

14. Linear Algebra

I need help please!! How many solutions does the system of equations have? 2x=-10y+6 and x+5y=3 a. one b. two c. infinitely many d. none y=4x+3 and y=4x+4 a. one b. two c. infinitely many d. none x-4y=12 and y=1/4x-3 a. one b. two c. infinitely many d.

15. Physics

A horizontal force, F1 = 85 N, and a force, F2 = 18.4 N acting at an angle of θ to the horizontal, are applied to a block of mass m = 2.1 kg. The coefficient of kinetic friction between the block and the surface is μk = 0.2. The block is moving to the

16. Maths

A quiz has 20 multiple choice questions, each with a choice of 4 answers. If Jay guesses an answer for each question at random, find the probability that he will score 75% on this quiz, correct to 2 significant figures. Answer: 0.000 003 4 Thanks for any

17. Math

Insert the missing digits to make number sentence true _,_63-3,9_9=2,83-

18. Math

A eighteen-sided die is rolled three times. In how many ways can this happen? How would I solve this problem?

19. math

Susie bought 5 kg of flour and 4 kg of sugar for \$14.80.If 3/4kg of flour cost as much as 3/5kg of sugar,find the cost of 1kg of sugar.

20. Geometry

In a triangle, we have line QR parallel to line ST, PQ = 8, QS = 6, and PT = 12. Find PR.

21. Physics

The diameter of the Moon is 3.78x10^6m. It subtends an angle of .00982 radians at the surface of Earth. How far is the Moon from Earth? (Please explain I can't wrap my head around this question.)

22. Maths

A circular lily pond is surrounded by a gravel walkway that is 4 m wide. Calculate the area of the walkway if the pond is 12 m in diameter.

23. chemistry

enthalpy change^H is +23kJ mol-1 of phosphine (PH3) for the reaction 2P(s)red+3H2(g)---->2PH3(g) a) Calc. entropy change for this reaction. Explain how this information allows you to determine the spontaneity or non-spontaneity of this reaction at any temp

24. Chemistry

2NaN3(s) −> 2Na(s) + 3N2(g) . If 0.65 mol of NaN3 reacts, what mass of nitrogen would result? Answer in units of g. Step by step with answer please! I'm begging!

25. History

One main difference between the Articles of Confederation and the U.S Constitution was that the Articles were very weak and the people had more power than the government while the Constitution gave more power to the government. Are there any other main

26. Maths

Two identical biased coins are tossed together, and the outcome is recorded. After a large number of trials it is observed that the probability that both coins land showing heads is 0.36. What is the probability that both coins land showing tails? Answer:

27. maths

There are 34 men and 32 women at a party. Of these, 13 men and 19 woman are married. If 2 people are chosen at random, find the probability that both will be men. Answer: 17/65 Thanks for any help

28. Maths

A cone shaped candle whose height is 3 times its radius is melting at the constant rate of 1.4 cm^3 s^-1. If the proportion of radius to height is preserved, find the rate at which the radius will be decreasing when it is 3.7cm. Answer: -0.01

29. Maths

A balloon is inflated so that its increase in volume is at a constant rate of 10cm^3 s^-1. If its volume is initially 1 cm^3, find its volume after 3 seconds. Answer: 31 cm^3

30. Maths

if seven workers dig a piece of ground in 10 days.How long will 5 workers take.

31. Chemistry

The fluoride ion concentration in a saturated solution of magnesium fluoride, MgF2, is 2.3 10-3 M. Calculate the value for the equilibrium constant.

32. Chemistry

SO2(g) + O2(g) → SO3(g) What volume of sulfur dioxide gas reacts with 15.0 L of O2? The reaction conditions are 875°C and 1.00 atm pressure

33. chemistry

a gas sample heated in a cylinder uses 650kJ of heat. a piston that compresses this gas does 800kJ of work. What is the change in internal energy, ^E of the gas during this process?

34. chemistry

the standard free energies of formation of SO2(g) and SO3(g) are -300.4 and -370.4kJ mol-1 respectively. Calculate the value of the equilibrium constant at 25'C for the reaction 2SO2(g)+O2(g)==>2SO3(g)

35. Math

Which coins would you use to make \$0.28? Write two ways

36. Chemistry

One enzyme- catalyzed reaction in a biochemical cycle has an equilibrium constant (K1) that is 10 times the equilibrium constant (K2) of a second reaction. If the standard Gibbs energy of the former reaction is - 300 kJ mol-1, what is the standard reaction

37. Math/ Number sense

Use the numbers shown. Make the sum of the numbers across equal the sum of the number down. 7 5 1 9 3

38. mathematics

in f(x)=ln(x/x-1) how would you write an exporession for f^-1(x), where f^-1(x) denotes the inverse of f(x)

39. Science

Genetic drift results in a change in gene frequencies because a. gene flow within the population is less than gene flow between populations. b. reproduction is non-random within the population c. the population size is so small that chance occurrences can

40. Physics

does anyone know what the rate of sound waves is for 12.6hz? Never mind got it

41. Maths

A spherical bath oil capsule dissolves in the bath so that its decrease in volume is proportional to its surface area. If its shape remains spherical as it dissolves, show that the radius of the capsule will decrease at a constant rate. Thanks to anyone

42. Health science

Branches of health education

43. Math

Please Check My Answers!!! What is the type of conic section is given by the equation x^2-9y^2=900 and what is the domain and range? Answer: Type is hyperbola, Domain is all real values of x, not sure what the range is. Please explain how to find these

44. physic

A coconut thrown horizontally at 20 m/s from the top of a hill 63 m high. How far from the base of the hill does the coconut hit the ground?

45. Math

MATHMATHMATH What letter is in the 30th position? I think it is A but I am not sure.

46. Physics

An airplane needs to accelerate at 4.7 m/s2 to reach take-off speed before reaching the end of the runway. The mass of the airplane is 4500 kg. How much force is needed from the engines?

47. mathematics

Candice makes gift boxes during her free time.She charges 40 cents for a triangular box,50 cents for a heart shaped box and a cylindrical box for 60 cents.Last Sunday,Candice sold 16 different types of boxes and collected a total of 8 dollars.How many of

48. math

Agus sold packets of sweets to Halim and Kairi in the ratio 8:13.He sold the sweets in 2-kg packets.What was the smallest possible mass of sweets Agus sold to both of them?

49. math

An architect is designing an office building with n floors that will have an FM radio antenna 15.85m tall on its roof. Each floor of the building will be 3.9m high. Which equation can be used to find the total height, h, of the building in meters,

50. Art... check

Which of the following is a convention Chinese artist Shen Zhou used in his brush paintings? He used only black ink to emphasize expressive brushstrokes. He painted several seated Buddha in the background. He painted flat, realistic figures to reflect

51. Trig

Two people decide to find the height of an obelisk. They position themselves 25 feet apart in line with, and on the same side of, the obelisk. If they find that the angles of elevation from the ground where they are standing to the top of the obelisk are

52. Math

A number whose digit in the ten billions place is 5 less than 8

53. Math

What are the solutions of the system? y = x2 + 3x – 4 y = 2x + 2 Don't understand

54. Chemistry

A sample of oxygen gas occupies 500.0 mL at -185°C and 75.0 cmHg. Calculate the temperature in °C if the gas has a volume of 221.0 mL at a 55.0 cmHg.

55. math

19 cars start a race. in how many ways can the top 3 cars finish

56. chemistry

list the following substances in order of increasing molar entropy at 25'c. H2O(l), H2O(g), H2O(s), C(s), Ar (g) Explain your reasoning

57. writing

I need help to write a summery for the open univercity please write for me one Thanks

58. science

A pressure vessel contains a large volume of CO2 gas at 10 atm pressure. A membrane composed of a poly(ether ketone) polymer with thickness 100 microns and net effective area of 100 cm2 covers a small perforated port in the container. The solubility of CO2

59. Physics

A force of 40 N is required to start a 5 kg box moving across a horizontal concrete floor. (a) What is the coefficient of static friction between the box and the floor? (b) If the 40 N force continues, the box accelerates at 0.70 m/s2. What is the

60. Math

Write a4-digit number that has a hundrens digit of 6, a tens digit of 3, and 9 for each of the other digits.

61. Math

Reasonableness. Use the clues to solve the. Riddle. I am between 24and34. You say my name when you count by twos from zero. You say my name when you count by fives from zero. What number am I? 20 21 22 23 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39

62. Chemistry

Phosphorous trichloride (PCl3) is produced from the reaction of white phosphorous (P4) and chlorine: P4(s) + 6Cl2(g) --> 4 PCl3(g) . A sample of PCl3 of mass 280.7 g was collected from the reaction of 70.86 g of P4 with excess chlorine. What is the

63. Sound and music

If the fundamental frequency for a 60-cm long guitar string is 500 Hz, what is the speed of the traveling waves?

64. English 2

In "It Can't Be Helped," why does Mama destroy her dishes? a)She does not like the pattern on the dishes, which are chipped anyway. b)Most of the other dishes have been broken in the move. c)She doesn't want the dealer to take advantage of her family's

65. Chemistry

What is the balanced net ionic equation for the following reaction: 2 NH4Cl + Ba(OH)2 = 2H2O + BaCl2 + 2 NH3 i got 2NH4^+ +2OH- = 2H2O + 2NH3 but it keeps telling me i'm wrong

you have 8 moving boxes that you can use to pack for college. each box holds 15 lbs of clothing or 60lbs of books. let c be the number of boxes that contain clothing. write a function that gives the total pounds T of the boxes in terms of the number of

67. Chemistry

The reaction of aqueous barium hydroxide and aqueous sodium sulfate is represented by the balanced net ionic equation. Ba2+(aq) + SO42-(aq) → BaSO4(s) Give the balanced ionic equation for the reaction. Include the states.

68. math

A school sells tickets for a show, (a) adult tickets and (c) child tickets. 1) each adult ticket costs \$8 and each child ticket costs \$5. the total takings are 2300. Write an equation to represent this information. 2) solve algebraically the simultaneous

69. Biology

Zucchini cores placed in sucrose solutions at 27oC resulted in the following percent changes after 24 hours: % change in mass [Sucrose] 20 distilled water 10 0.2 M -3 0.4 M -17 0.6 M -25 0.8 M -30 1.0 M Graph the results and find the molar concentration of

70. Government/Economics

The bank of the UNited States is: A. U.S. Bank B. First National Bank C. Bank of America D. Seafirst E. None of the Above If anything, the bank of the U.S. would be the Federal Reserve. I would go with E There were in actuality two different Banks of the

71. math

Hi. Please help me with this?: Suppose you start a home business typing technical research papers for college students. You must spend \$3500 to replace your computer system. Then you estimate the cost of typing each page will be \$.02. Write a rational

72. algebra

Find the points of discontinuity and any holes. y=x^2-1/(x^2+3x+2) please and thank you y =(x^2-1)/((x+1)(x+2)) =(x-1)/(x+2) we cancelled the (x+1)/(x+1) which is 0/0 for x=-1 so in our simplified expression when x=-1 y = -2 There is a "hole" at (-1,-2) in

73. chemistry

A hydrate of strontium choloride contains 40.54% water. What is the formula of the hydrate ? SrCl2*xH2O. H2O = 40.54% SrCl2 = 100 - 40.54 = 59.46% Take 100 g sample. This gives us 59.46g SrCl2 and 40.54g H2O. Convert to mols. mols SrCl2 = 59.46/158.5 =

74. Physics

How much work is done by a tree to stop a 25.0 g arrow traveling at 75.0 m/s if it embeds itself 6.00 cm into the trunk?

75. Economics

If the MPC is .8 and the government increases both spending and lump-sum taxes by \$100 million, then we would expect: a) an increase in total income of \$500 million b) a reduction in equilibrium income of \$80 million c)an increase in equilibrium income of

76. Maths

Two fair dice are thrown. If the first die thrown is a 3, what is the probability that the sum of the two dice is greater than 7? Answer: 1/3. Thanks for any help

77. Maths

In a class of 30 girls, 13 are dancers and 23 are gymnasts. If 7 girls do both dance and gymnastics, what is the probability that a girl chosen at random does neither dance nor gymnsatics. Answer: 1/30 Thanks to anyone who helps

78. Maths

A set of 5 cards, each labeled with the letters A, B, C, D and E, is placed in a hat and two selected at random without replacement. Find the probability of getting D and E. Answer: 1/10 Thanks for any help

79. Maths

In Yahtzee, 5 dice are rolled. Find the probability of rolling at least one 6. Answer: 4651/7776 Thanks for any help

80. math

A stone is dropped from a building 50 m high. Its acceleration at any time, t, can be approximated by the equation a = -10. How long does it take for the stone to hit the ground at the foot of the building? Can someone please help me with this. Thanks in

81. Maths

A stone is dropped from a building 50 m high. Its acceleration at any time, t, can be approximated by the equation a = -10. How long does it take for the stone to hit the ground at the foot of the building? Answer: 3.16 s

82. Maths

If a rockets acceleration is given by a=-k/x^2, where x is the distance from the centre of the Earth, and if the rocket starts from rest at the surface of the Earth (radius 6400 km), find an equation for the velocity of the rocket in terms of x. Answer: v

83. Maths

The velocity of a particle is given by v= t / t^2+3 ms^-1. If the particle is initially at the origin, find its displacement after 10s, correct to 2 decimal places. Answer: 1.77 m

84. maths

The rate of flow of water into a dam is given by R=500+20t L h^-1. If there is 15 000L of water initially in the dam, how much water will there be in the dam after 10 hours? Answer: 21 000L

85. Maths

If (1+px)^n = 1 + 15x +90x^2 +... , find the values of p and n. Answer: p=3, n=5 Thanks for any help

86. Maths

Find the area enclosed by the curves y=x^2 and x=y^2. Thank you to any who helps

87. algebra

Solve the following system of equations. You will type your x value in the first part and the y value in the second part of the question. If the answer is no solution then type NS in both parts and if the the answer is infinite solutions then type I in

88. physics

A hockey puck was moving at +22.8m/s. When it hit the goalie's glove, it showed down and came to a stop in +0.10m. a) How far was the player from the goalie if it took 0.30s to travel from the player's stick to the goalie's glove? b) How long did it take

89. Math

Find F(t) such that F'(t)= Sec^4 (t) and F (pi/4) = 0

90. Math

How would you solve this problem? Please include steps for me! Solve for θ in the interval 0 ≤ θ ≤ 2π: cos(θ )sin(θ ) − 1/ 2cos(θ ) = 0

91. Math

There are 14 NBA teams who do not make the playoffs. Of these teams, 3 of them will be randomly selected to make the 1st, 2nd, and 3rd pick. How many different ways can the 1st-3rd pick be arranged?

92. Math

For questions 2 and 3, use a calculator to find the values of the inverse function in radians. sin^-1(0.65) 0.71 + 2pi n and –0.71 + 2 pi n 0.71 + 2 pi n and –3.85 + 2 pi n 0.86 + 2pi n and –0.86 + 2pi n –0.61 + 2pi n and 2.54 + 2 pi n

93. Algebra

Suppose you are researching the eating habits of people your age. What sampling method could you use to find the percent of students in your grade who eat five servings of fruit and vegetables each day? What is an example of a survey question that does not

94. Math

Suppose you are researching the eating habits of people your age. What sampling method could you use to find the percent of students in your grade who eat five servings of fruit and vegetables each day? What is an example of a survey question that does not

95. Physics

A telescope has an objective with a refractive power of 1.65 diopters and an eyepiece with a refractive power of 240 diopters. What is the angular magnification of the telescope?

96. Science

what is the name of the structure that air passes through when going to lungs from mouth in the frog?

97. Algebra

To help open a jewelry store, Chang borrowed money from his credit union. He took out a personal, amortized loan for \$45,000, at an interest rate of 6.45%, with monthly payments for a term of 8 years. For each part, do not round any intermediate

98. physics

A champion discus thrower throws a discus with an initial speed of 26 m /s. If the discus is thrown upward at an angle of 45o, what maximum height and what range will the discus attain? What is its time of flight? For the sake of simplicity, ignore the

99. Math

Fill the bracket with +,-,×,÷. 16 () 10 () 2 () 5 = 20 What is the answer? I have tried for 1 hour but I do not know the answer.