## Most Popular Questions of 2013

1. ### Chemistry

Consider the following reaction: 2Fe2O3 --> 4Fe + 3O2 ∆Hrxn° = +824.2 kJ The decomposition of 29.0 g of Fe2O3 results in a. the release of 150 kJ of heat b. the release of 12000 kJ of heat c. the absorption of 12000 kJ of heat d. the absorption of 150

asked by Anonymous on September 21, 2013
2. ### precalculus

Outside temperature over a day can be modelled as a sinusoidal function. Suppose you know the temperature is 80 degrees at midnight and the high and low temperature during the day are 90 and 70 degrees, respectively. Assuming t is the number of hours since

asked by marie darling on March 26, 2013

1. Which line models the data points better and why? blue, because the data points are all close to the line red, because it goes through one of the points i think that is A

asked by batman on March 22, 2013
4. ### Math help

You buy 3 pounds of organic apples for \$7.50. The graph shows the price for regular apples. What is the unit rate for each type of apples?

asked by Mr.Brain on May 2, 2013
5. ### Math for Ms. Sue please! Last math questions!

1. What is the term for data that are grouped closely together? (1 point) outlier linear positive clustering 2. What association would you expect if graphing height and weight? (1 point) positive nonlinear negative none of these 4. What association would

asked by Delilah on March 15, 2013

1. Write a function rule for finding the amount of daily pay, p, in the following situation: A bus driver gets paid \$100 each day plus \$0.20 per kilometer, k. (1 point) 100 = 0.20 × k p = 0.20 × 100 × k p = 0.20k + 100 0.20k = 100 + p 4. Write a

asked by Delilah on April 19, 2013
7. ### Chemsitry

The Ksp of PbBr2 is 6.60× 10^–6. What is the molar solubility of PbBr2 in pure water? What is the molar solubility of PbBr2 in 0.500 M KBr solution? What is the molar solubility of PbBr2 in a 0.500 M Pb(NO3)2 solution?

asked by Anon on March 17, 2013
8. ### Chemistry

For the following chemical reaction... HCN (aq) + KOH (aq)----> H2O (l) + KCN (aq) write the net ionic equation, including the phases

asked by Chelsea on October 4, 2013
9. ### Science--HELP!!

1. In which of the following situations is a sound wave most likely to travel through air? A) An alarm clock rings in a vacuum. B) A giant star explodes. C) A grasshopper eats a leaf. D) An astronaut uses tools in space. 2. Which of the following factors

asked by Jasmine on December 9, 2013
10. ### Pre-Algebra

1. What data are represented by the stem-and-leaf plot below? 3 | 7 8 9 4 | 1 3 7 5 | 2 4 Key: 4 | 1 means 41 a. 37, 38, 39, 41, 43, 47, 52, 54 b. 73, 83, 93, 14, 34, 74, 25, 45 c. 7, 8, 9, 1, 3, 7, 2, 4 d. 37, 38, 39, 14, 34, 74, 25, 45 2. Find the mode

asked by Janessa on March 20, 2013
11. ### Math Ms. Sue please

1. You flip a coin 30 times and get heads 11 times, so the chance of getting heads is eleven over thirty . Is this an example of theoretical or experimental probability? (1 point) theoretical experimental 2. You have made 3 out of 10 of your last free

asked by Delilah on April 9, 2013
12. ### creating a pivot table

before you create a pivot table, it is important to ________.

asked by NoS aSSaSSiNx on November 25, 2013
13. ### Pre-Algebra

1) Find the surface area for a sphere with a radius of 10 feet. Round to the nearest whole number. a. 1,256 ft2 b. 4,189 ft2 c. 1,089 ft2 d. 1,568 ft2 2) Find the volume of a sphere with a radius of 10 feet. Round to the nearest whole number. a. 1,257 ft3

asked by Alexa on March 13, 2013
14. ### algebra

Could someone check my work; 1. Generate the first five terms in the sequence using the explicit formula. yn = –5n – 5 –30, –25, –20, –15, –10 30, 25, 20, 15, 10 –10, –15, –20, –25, –30(my answer) 10, 15, 20, 25, 30 2. What is the

asked by lee on February 3, 2013
15. ### help plz? 2 questions

1. What does it mean to calculate frequencies within a dataset? to count the number of times a dataset is used by a student to calculate the product of two variables to make a third variable to count the number of cases that fall into different subgroups

asked by Princess Anna on December 17, 2013
16. ### Math

1. 5h – 9 = –16 + 6h (1 point) 4 –7 7 10 2. 4x + 4 = 9x – 36 (1 point) –8 –7 8 –3 3. Which of the following equations has an infinite number of solutions? (1 point) 3x – 3 = –4x 2y + 4 – y = 16 7x + 5 = 4x + 5 + 3x 6y – 2 = 2(y – 1)

asked by plz help on January 11, 2013

1.Find the lateral area of a cone with a radius of 7 ft. and a slant height of 13 ft. Use 3.14 for ð and round to the nearest tenth. 439.6 ft2 324.5 ft2 571.5 ft2 285.7 ft2 2.Find the surface area of a square pyramid with a base length of 24 cm and a

asked by Deliah on March 14, 2013
18. ### Chemistry

For the following, 2HBr (aq) + Ba(OH)2 (aq) ---> 2H2O (l) + BaBr2 (aq) write the net ionic equation including the phases

asked by Chelsea on October 4, 2013

Which of the following statements about radioactive dating is true? a. Radioactive decay is the rate at which new atoms form. b. During radioactive decay, atoms break down, releasing particles or energy. c. The rate of decay of a radioactive element cannot

asked by Anonymous on October 10, 2013
20. ### science

which of the following is the best course of action when it comes to using natural resources

asked by jose on November 7, 2013
21. ### Math

1. What type of graph does not show the number of times a response was given? (1 point) box-and-whisker plot line plot stem-and-leaf plot bar graph 2. Which of the following types of information is suited for display on a scatter plot? (1 point)

asked by Anonymous on April 5, 2013
22. ### Chemistry

For each electron in a ground-state Be atom, select the set of quantum numbers that represents it. Check all that apply. n=1 l=0 ml=-1 ms= +1/2 n=1 l=0 ml=0 ms=-1/2 n=2 l=1 ml=0 ms= -1/2 n=1 l=0 ml=0 ms=+1/2 n=2 l=1 ml=1 ms=+1/2 n=2 1=0 ml=0 ms=+1/2 n=2

asked by Anonymous on March 24, 2013
23. ### Science

Which of the following explains why a bone in a bird’s wing is homologous to a bone in a lizard’s front leg? a.The bones in the two species provide for the same type of motion. b.The bones in the two species are both vestigial structures. c.The two

asked by Anonymous on November 10, 2013
24. ### science help plzzz

Multiple Choice 1. Which of the following images shows a living organism interacting with a biotic factor in its environment? (1 point) bird drinking water koala eating leaves plant in the Earth whale in the ocean 2. Which of the following shows the

asked by josh on November 7, 2013
25. ### Science help! URGENT. Check answers

1. True or False: If the net force of an object is 0 N, the forces are considered unbalanced. (True) 2. Which of the following forces causes a feather to fall slower than a blowing ball? gravity ← rolling friction sliding friction air resistance 3. A

asked by Elena on October 21, 2013
26. ### Science help! URGENT. Check answers

1. True or False? A model train traveling at a constant speed around a circular track has a constant velocity. (False) 2.Which of the following would be affected if a soaring eagle changed direction but remained at a constant speed? acceleration only

asked by Elena on October 15, 2013
27. ### Chemistry

At 25C only .0190 mol of the generic salt AB2 is soluble in 1.00L of water. What is the Ksp of the salt at 25C? AB2A^2+ + 2B^- I took the .0190 mol and doubled it and multiplied by .019 again and got 6.859x10^-6 and got it wrong what should I do? Please

asked by Cat on July 20, 2013
28. ### Math

Explain how to write a function rule from the table below. Then write a function rule. x 2 4 6 y 1 0 –1 I don't get these Please help.

asked by Slick Silver on April 16, 2013

Please check my work thanks!! A number cube with the numbers 1 through 6 is rolled. Find the given probability. 1. P(number < 2) (1 point) A. 1/6

asked by Matthew on March 6, 2013

Multiple Choice: 1. If a kestrel eats a mouse that eats grass, the kestrel is a (1 point) producer. second-level consumer. first-level consumer. decomposer. 2. Which of the following best explains why a species of lizard is able to live in the desert but

asked by josh on December 11, 2013
31. ### Chemistry

Which of the following will be more soluble in an acidic solution than in pure water? AgI, Ni(OH)2, KClO4, SrSO4, CaCO3

asked by Mandy on December 5, 2013
32. ### Science help (just 4 questions)

1. Which of the following is an example of an environmental pressure? (1 point) the air pressure in the atmosphere a lake that is gradually running out of water a fight between two members of the same species breeding between two members of the same

asked by Miley23 on December 4, 2013
33. ### chem

A ground state hydrogen atom absorbs a photon of light having a wavelength of 92.30 nm. It then gives off a photon having a wavelength of 384 nm. What is the final state of the hydrogen atom? Values for physical constants can be found here.

asked by Anonymous on October 19, 2013
34. ### Math Help? Check my answers.

1. You mix the letters: S E M I T R O P I C A and L thoroughly. Without looking you draw one letter. Find the probability that you select a vowel. From a fraction to simplest form. 12/5 5/12 1/3 7/12 2. You roll a standard cube once. Fine P(0) 7/6 1 1/2 0

asked by Rebekah on May 14, 2013
35. ### math

I need the answers to the why did the banana go out with the prune worksheet. I already have the answer to the riddle, but I need the numeral answers please.

asked by kk on October 6, 2013
36. ### algebra

Can someone check my answers on exploring conic sections? 1. Graph x2 + y2 = 9. What are its lines of symmetry? Every line through the center is a line of symmetry. The y-axis and the x-axis are lines of symmetry.( my choice) Every line through the center

asked by Lee on February 19, 2013
37. ### Physics

Problem 2- A 350 kg roller coaster starts from rest at point A and slides down the frictionless loop-the-loop shown in the figure. a) How fast is the roller coaster moving at point B? b) How hard does it press against the track at point B?

asked by Anonymous on December 12, 2013
38. ### tyndall

1. In the middle of the page, draw two vertical lines an inch long, an inch apart, and that are parallel to each other. 2. About a half inch below the lines, draw a half-inch horizontal line that is centered between the lines. 3. Draw a line from the

asked by ferdinand on September 7, 2013
39. ### calculus

A potter forms a piece of clay into a right circular cylinder. As she rolls it, the height h of the cylinder increases and the radius r decreases. Assume that no clay is lost in the process. Suppose the height of the cylinder is increasing by 0.5

asked by mike on March 31, 2013
40. ### Chemistry

Write a balanced net ionic equation (include physical states) for the following reaction: HClO2(aq)+NaOH(aq)=H2O(l)+NaClO2(aq)

asked by Kierra on July 24, 2013
41. ### Language Arts

1) Which of the following is an example of subjunctive verb mood? Going outside in your bare feet could make you cold. Will you go away? If I make the baseball team, I will skip around the field.*** The bread was old and crusty. 2) Which of the following

asked by Gabby on September 17, 2013
42. ### Science

Darwin assumed that evolutionary change was always slow and gradual. What was the first evidence that suggested evolutionary change might happen fast sometimes? a. homologous structures b. fossils c. reproduction rates d. DNA sequences Which of the

asked by Anonymous on November 14, 2013
43. ### Science

1. Which of the following traits is acquired A. the number of petals that grow in a plant's flowers B. the wing shape of a wild bird C. the ability of some gorillas to use sign language D. a cheetah's ability to run faster than any other animal 2. The

asked by homework help on December 13, 2013
44. ### Chemistry

A 0.110-L sample of an unknown HNO3 solution required 52.1 mL of 0.150 M Ba(OH)2 for complete neutralization. What was the concentration of the HNO3 solution?

asked by Lori on November 9, 2013
45. ### Math

1. Rosa, Roberto, Andrea, and Inno find an estimate for square root 10. Who has proposed the best solution? (1 point) Rosa: "Use square root 9 and square root 25 to estimate." Roberto: "I will use square root 4 and square root 9." Andrea: "It should be

asked by anonymous on December 1, 2013
46. ### Chemistry

Write a chemical equation representing the second ionization energy for lithium. use e- as the symbol for an electron.

asked by anonymous on April 1, 2013
47. ### Educational Technology

What does it mean to say that a country's land area is positively correlated with its population? a) The larger the land area of a country, the higher its population tends to be. b) The smaller the land area of a country, the higher its population tends to

asked by Dayana on November 21, 2013

1.which of the following were found to destroy ozone in the upper atmosphere? A. sulfur oxides B. cfcs(i pick this) C. nitrogen oxides D. carbon dioxide 2.which of the following sets of terms is associated with air pollution caused by burning fossil fuels?

asked by matt on December 20, 2013
49. ### Science~

asked by Marie on October 8, 2013
50. ### MATH

In Marissa's Calculus course, attendance counts for 5% of the grade, quizzes count for 15% of the grade, exams count for 60% of the grade, and the final exam counts for 20% of the grade. Marissa had 100% average for attendance, 93% for quizzes, 82% for

asked by Kristina on January 27, 2013
51. ### Math~Polynomials

1)6g+8k-9g+2k(1point) 3g+10k -3g+10k*** 17gk 10k-3 2)-4x+6x^2+5x(1point) 7x^3*** 6x^2+9x 6x^2-9x 6x^2+x 3)a^2+5a-3a^2(1point) 5a+2a^2 -2a^2+5a*** -3a^2+6a 5a-3a^2 4)3x^2+8x+7x(1point) 3x^2+15x*** 18x^3 3x^2+1 3x^2-x 5)Find the degree of

asked by Gabby on May 13, 2013
52. ### Check my Science questions?

1. Why is it rare for the soft parts of an organism to become a fossil? The soft parts take a long time to decay. The soft parts can be eaten by other animals. The soft parts cannot be buried in sediment. The soft parts form petrified fossils. 2. Which of

asked by Princess Anna on December 11, 2013
53. ### Chemistry

how do i write the complete electron configuration for Ga3+ and Mg2+????????????

asked by mariana on August 4, 2013

1. What is the simplified form of squared root 140? A.) 4 to the square root of 35 B.) 10 to the square root of 14 C.) 2 to the square root of 70 D.) 2 to the square root of 35 Please show me how to do this Thank You

asked by Jim on March 12, 2013
55. ### Physics

A 1000N crate is being pushed across a level floor at a constant speed by a force F of 300N at an angle of 20.0 degrees. (a) What is the coefficient of kinetic friction between the crate and the floor? (b) If the 300-N force is instead pulling the block at

asked by DROSP on November 14, 2013
56. ### math

A box with an open top has vertical sides, a square bottom, and a volume of 256 cubic meters. If the box has the least possible surface area, find its dimensions.

asked by kitor on June 4, 2013
57. ### physics

A 60.0-kg skier with an initial speed of 12.0 m/s coasts up a 2.50-mhigh rise and angle is 35 degrees.Find her final speed at the top, given that the coefficient of friction between her skis and the snow is 0.0800. (Hint: Find the distance traveled up the

asked by Amy on July 14, 2013
58. ### 8need a function rh grade math

a 154 lb person burns 420 calories per hr riding an exercise bike at 15 mph. Need a function rule to represent the total calories burned over time.

asked by Jane on May 14, 2013
59. ### PHYSICS

express dissipated power in terms of voltage and resistance. express dissipated power in terms of current and resistance

asked by preya on September 8, 2013
60. ### physics

A pulley is suspended by a Cord (C). on one end of the pulley there is a 1.2 kg block and on the other is a 3.2 kg block.Determine the tension in this cord after the masses are released and before one hits the ground. Ignore the mass of the pulley and

asked by Anonymous on February 14, 2013
61. ### math

Find the area of the regular polygon. Round your answer to the nearest tenth. the individual sides are 10 the radius is 13.07

asked by rebecca on May 4, 2013
62. ### Microeconomics

ADVANCED ANALYSIS Assume the following values for Figures 5.4a and Figures 5.4b. Q1 = 20 bags. Q2 = 15 bags. Q3 = 27 bags. The market equilibrium price is \$45 per bag. The price at a is \$85 per bag. The price at c is \$5 per bag. The price at f is \$59 per

asked by Mary on January 19, 2013
63. ### General Chemestry

A galvanic (voltaic) cell consists of an electrode composed of chromium in a 1.0 M chromium(II) ion solution and another electrode composed of gold in a 1.0 M gold(III) ion solution, connected by a salt bridge. Calculate the standard potential for this

asked by Anonymous on January 26, 2013
64. ### Health

1. It is not possible to get a good workout at home. True *False 2. Most home equipment is expensive. *True False 3. A treadmill is a good choice of home equipment for a person who wants to improve their cardiovascular fitness. *True False 4. Something as

asked by Anonymous on May 2, 2013
65. ### algebra

What is the quotient in simpliest form? State any restrictions on the variable. x+2/x-1 divided by x+4/x^2+4x-5. My answer (x+2)(x+5)/x+4; don't get the restriction part either -5,-4 or 1,-4,-5 Can someone please help?

asked by dirtrider on January 23, 2013
66. ### science help!!!

1. Seahorses change color and swim together in predetermined ways before mating. These behaviors are called (1 point) asexual reproduction. sexual reproduction. courtship rituals. budding. 2. A male peacock displays his colorful tail feathers in order to

asked by josh on October 18, 2013
67. ### Maths

Prove that max & min values of asinx+bcosx are =/- (a^2+b^2)^1/2

asked by Alok on July 12, 2013
68. ### math

a weather forecaster predicts that the temperature will drop 3 degrees each hour for the next 9 hours. If the temperature is 7 degrees farenheit before the temperature starts falling, what is the temperature after the drop?

asked by Arlene on September 8, 2013
69. ### science help plzzz

Multiple Choice 1. At the chromosomal level, what is the difference between human males and human females? (1 point) All males have a Y chromosome, and females do not. All males have an X chromosome, and females do not. All males have 47 chromosomes, and

asked by josh on October 29, 2013
70. ### Math

What is the rounded off number,to the nearest gram,of 4.86932 kg

asked by Oliver on July 5, 2013
71. ### chemistry

A commercially available sample of sulphuric acid is 15% H2SO4 by mass (density=1.10g/ml) Calculate the molarity ,normality and molality.

asked by riya on June 3, 2013
72. ### Physics

A 20 kg crate is placed on a horizontal conveyor belt. The materials are such that us = 0.47 and uk = 0.21. What is the maximum acceleration the belt can have without the crate slipping? If acceleration of the belt exceeds the value determined in part A,

asked by Leanna on March 3, 2013
73. ### chemistry

Complete the two reduction half reactions for the cell shown at the right, and show the line notation for the cell by dragging labels to the correct position. (The electrode on the left is the anode, and the one on the right is the cathode.) They give you

asked by shanonn on May 5, 2013
74. ### science

which of the following could be true of two different species that have a competitive relationship in the same ecosystem? A.one species preys on the other B.they relationship is mutually beneficial C.they share the same niche D.one species benefits, while

asked by Aaron on December 13, 2013
75. ### statistics

the life spans of three randomly selected tires are 31,400 miles, 40,600 miles and 36,000 miles. Using the empirical rule, find the percentile that corresponds to each life span.

asked by cynthia on September 8, 2013
76. ### algebra

6k-4k=6

asked by Francine on September 8, 2013

1. The ordered pairs (1, 1), (2, 8), (3, 27), (4, 64), and (5,125) represent a function. What is a rule that represents this function? Y = x Y = 4x Y = x^2 Y = x^3 I don't know how to solve this please help!

asked by Charlotte on November 7, 2013
78. ### math check answer plz

you earn \$7.50 per hr to help ur uncle in his shop. you earn \$33.75 . write and solve an equation to find how may hrs u worked. I put \$7.50 x hours= \$33.75 and hours is 4.5 is that correct?

asked by scooby on September 8, 2013
79. ### Science

what the difference between the structures of simple and complex

asked by Alex on September 8, 2013
80. ### math

what are the 5 number combo in 1 to 39

asked by william on September 8, 2013
81. ### MATH

Question: The pair of polygons is similar. Find the value of x. Could anyone please explain how to find x? Thanks in advance!

asked by Deejay Kratz on January 9, 2013
82. ### math check if right plz

your schools football team scored 49 points. your team score was 19 points more than your opponent scores. write and solve an equation to find the opponents score is this right. 49-19=s and s would be 30?

asked by scooby on September 8, 2013
83. ### Science help.....

Explain why Earth and other planets were not solid when they formed during the beginning of the Precambrian, approximately 4,600 million years ago (MYA). What was this particular time period called, and why is this time period not really considered a

asked by Princess Anna on December 30, 2013
84. ### math

How can I solve for x? 3x - 4 = 17

asked by Francine on September 8, 2013
85. ### chemistry

Write the equation for the decomposition of water into its elements. Phase symbols are not graded.

asked by lee on April 17, 2013
86. ### math

Generate the first five terms in the sequence using the explicit formula. cn= 12n – 11 (1 point)

asked by paige on February 26, 2013
87. ### statistics

Assume that blood pressure readings are normally distributed with a mean of 123 and a standard deviation of 9.6. If 144 people are randomly selected, find the probability that their mean blood pressure will be less than 125.

asked by florence on October 14, 2013
88. ### math Ms. Sue please

3. Which of the following examples would show a negative trend? (1 point) height and weight of students test scores and height of students outside temperature and heating bill none of these Is the answer " test scores and height of students"?

asked by Delilah on March 15, 2013

1. What is the degree of the monomial 3x2y3? 2 3 5 6 2. What is the simplified form of 8b3c2 + 4b3c2? 12bc 12b3c2 12b6c4 12b9c4 3. What is the simplified form of (4j2 + 6) + (2j2 – 3) ? (1 point) (0) 6j2 – 3 (1) 6j2 + 3 (0) 6j2 + 9 (0) 4j4 + 3 4. What

asked by Deborah on January 28, 2013
90. ### Math

Show how to make one addend the next tens number. Complete the new addition sentence. My son doesn't remember how to do this and I am confused? First one is 15 + 37 = 52 so it's asking the next tens would this be 10 + 42 = 52 would it always be 10? Please

asked by Nikol on October 23, 2013
91. ### chemistry

Suppose you take a trip to a distant universe and find that the periodic table there is derived from an arrangement of quantum numbers different from the one on Earth. The rules in that universe are: 1. principal quantum number n = 1, 2, . . . (as on

asked by Anonymous on April 2, 2013
92. ### Chemistry

Ba(OH)2 is a strong electrolyte. Determine the concentration of each of the individual ions in a 0.700 M Ba(OH)2 solution. I know that Ba(OH)2 -> Ba + 2OH But how do I determine the concentrations? I feel like I am making this more complicated than need be

asked by Hana on April 8, 2013
93. ### chemistry

Identify the neutral element represented by this excited-state electron configuration, then write the ground-state electron configuration for that element. Excited State: 1s2 2s2 2p2 3s1 Element Symbol: ? Ground State: ?

asked by Kim on September 30, 2013
94. ### physics

A block is at rest on the incline shown in the figure. The coefficients of static and ki- netic friction are μs = 0.45 and μk = 0.38, respectively. The acceleration of gravity is 9.8 m/s2 . What is the frictional force acting on the 25 kg mass? Answer in

asked by Anonymous on October 1, 2013

Can you help me with the sentence check 2 Chapter 17 and 18 in the improving vocabulary skill workbook?

asked by lisa on January 27, 2013
96. ### calculus 1

A kite 100 ft above the ground moves horizontally at a speed of 10 ft/s. At what rate is the angle (in radians) between the string and the horizontal decreasing when 200 ft of string have been let out?

asked by heather on February 26, 2013
97. ### Math

13. A catapult launches a boulder with an upward velocity of 148 ft/s. The height of the boulder (h) in feet after t seconds is given by the function h = –16t² + 148t + 30. How long does it take the boulder to reach its maximum height? What is the

asked by Jim on March 11, 2013
98. ### Science

What could the relative age of two rocks tell you about them? a. One rock is 10,000 years old, and the other is 8,000 years old. b. One rock is older than the other. c. They both have fossils in them. d. One rock is closer to the surface than the other.

asked by Anonymous on October 8, 2013
99. ### Algebra

Determine whether each sequence is arithmetic or geometric. Find the next three terms. 14, 19, 24, 29, . . . A.geometric, 34, 39, 44 B.arithmetic, 32, 36, 41 C.arithmetic, 34, 39, 44 D.The sequence is neither geometric nor arithmetic. I think this is C...?

asked by Cassie on March 19, 2013
100. ### Math

1. What are the steps to solve this problem? 0.000027 ÷ 0.000009 Requirements: • Explain how to use scientific notation to solve the problem. • Describe how to divide numbers written in scientific notation. • Give you final answer in simplest form.

asked by anonymous on November 14, 2013