Mel

Most popular questions and responses by Mel
1. calc

Given the position function, s of t equals negative t cubed divided by 3 plus 13 times t squared divided by 2 minus 30 times t, between t = 0 and t = 9, where s is given in feet and t is measured in seconds, find the interval in seconds where the particle

asked on January 8, 2016
2. Quick calc question

The Riemann sum, the limit as the maximum of delta x sub i goes to infinity of the summation from i equals 1 to n of f of the quantity x star sub i times delta x sub i , is equivalent to the limit as n goes to infinity of the summation from i equals 1 to n

asked on February 11, 2016
3. chem

Combustion reactions involve reacting a substance with oxygen. When compounds containing carbon and hydrogen are combusted, carbon dioxide and water are the products. Using the enthalpies of combustion for C4H4 (-2341 kJ/mol), C4H8 (-2755 kJ/mol), and H2

asked on November 27, 2007
4. physics

Hey can someone help with this. A movie stuntwoman drops from a helicopter that is 30.0 m above the ground and moving with a constant velocity whose components are 10.0 m/s upward and 15.0 m/s horizontal and toward the south. You can ignore air resistance.

asked on September 26, 2008
5. physics

A 5 kg block is placed near the top of a frictionless ramp, which makes an angle of 30o degrees to the horizontal. A distance d = 1.3 m away from the block is an unstretched spring with k = 3000 N/m. The block slides down the ramp and compresses the

asked on March 11, 2012
6. Quick calc question

Which of the following definite integrals could be used to calculate the total area bounded by the graph of y = 1 – x2 and the x-axis? the integral from 0 to 1 of the quantity 1 minus x squared, dx plus the integral from 1 to 2 of the quantity 1 minus x

asked on February 12, 2016
7. math-calculus

A spherical party balloon is being inflated with helium pumped in at a rate of 12 cubic feet per minute. How fast is the radius growing at the instant when the radius has reached 1 ft?

asked on December 17, 2012
8. Quick calc question

Use geometry to evaluate the integral from 0 to 10 of the function f of x, dx for f of x equals 5 for x less than or equal to 5 and equals the quantity 10 minus x for x greater than 5 . 12.5 25 37.5 Cannot be found

asked on February 16, 2016
9. chem

A piece of solid carbon dioxide, with a mass of 6.2 g, is placed in a 4.0 L otherwise empty container at 21°C. ( a) What is the pressure in the container after all the carbon dioxide vaporizes? atm (.86 atm) (b) If 6.2 g solid carbon dioxide were placed

asked on November 17, 2007
10. chem

One mole of H2O(g) at 1.00 atm and 100.°C occupies a volume of 30.6 L. When one mole of H2O(g) is condensed to one mole of H2O(l) at 1.00 atm and 100.°C, 40.66 kJ of heat is released. If the density of H2O(l) at this temperature and pressure is 0.996

asked on November 26, 2007
11. physics

A block weighing 8.3 N requires a force of 2.6 N to push it along at constant velocity. What is the coefficient of friction surface? A weight W is now placed on the block and 8.2 is needed to push them both at constant velocity. What is the weight W of the

asked on March 19, 2010
12. chem

You are given the following data. P4(s) + 6 Cl2(g) 4 PCl3(g) H = -1225.6 kJ P4(s) + 5 O2(g) P4O10(s) H = -2967.3 kJ PCl3(g) + Cl2(g) PCl5(g) H = -84.2 kJ PCl3(g) + 1/2 O2(g) Cl3PO(g) H = -285.7 kJ Calculate H for the following reaction. P4O10(s) + 6

asked on December 1, 2007
13. Physics

Find an expression in terms of M, mu, and theta for the speed of waves on the string.Express your answer in terms of the variables M, mu, theta, and appropriate constants. The picture shown is just of a block with mass m on an inclined frictionless surface

asked on November 27, 2012
14. CHEMISTRRY

What is the molarity of an HCl solution if 49.0 mL is completely titrated by 68.4 mL of an NaOh solution whose concentration is 0.333 M?

asked on June 8, 2010
15. Calculus

Water is drained out of tank, shaped as an inverted right circular cone that has a radius of 16cm and a height of 8cm, at the rate of 4 cm^3/min. At what rate is the depth of the water changing at the instant when the water in the tank is 6 cm deep? Show

asked on January 8, 2016
16. Quick calc question

Use geometry to evaluate the integral from 0 to 10 of the function f of x, dx for f of x equals 5 for x less than or equal to 5 and equals the quantity 10 minus x for x greater than 5 . 12.5 25 37.5 Cannot be found

asked on February 12, 2016
17. Social studies

Which of the following phrases might a Republican Congress have used to describe President Johnson's Reconstruction plans

asked on January 24, 2017
18. chem

calculate the max wavelength of light capable of removing an electron for a hydrogen atom from the energy state characterized by the following : n=2 in nm n=4 in nm

asked on December 6, 2007
19. Quick calc question

Use the table below to evaluate the derivative with respect to x of g of f of 2 times x at x = 1. x 1 2 3 4 f(x) 6 1 8 2 f ′(x) 6 1 8 2 g(x) 1 4 4 3 g ′(x) 9 5 5 –4

asked on January 30, 2016
20. Quick calc question

A particle moves on a line away from its initial position so that after t hours it is s = 4t^2 + t miles from its initial position. Find the average velocity of the particle over the interval [1, 4]. Include units in your answer.

asked on January 29, 2016
21. help!

2cr(s) + SnCL4(aq) --> can this reaction occur if so write the balanced equation if it doesnt explain why

asked on April 16, 2009
22. Quick calc question

For f of x equals the quotient of the quantity 1 minus x and the quantity 1 plus x and g of x equals the quotient of the quantity x and the quantity 1 plus x, find the simplified form for f [g(x)] and state the domain.

asked on January 30, 2016
23. physics

A shell is fired from the ground with an initial speed of 1.58 103 m/s at an initial angle of 31° to the horizontal. (a) Neglecting air resistance, find the shell's horizontal range. m (b) Find the amount of time the shell is in motion. s

asked on November 18, 2012
24. calc

A particle moves along the x-axis with position function s(t) = e^(cos(x)). How many times in the interval [0, 2π] is the velocity equal to 0? 1 2 3 More than 3< my nswer

asked on January 28, 2016
25. Calculus

The side of a square is measured to be 10 ft with a possible error of ±0.1 ft. Use differentials to estimate the error in the calculated area. Include units in your answer.

asked on January 8, 2016
26. chem

On Easter Sunday, April 23, 1983, nitric acid spilled from a tank car near downtown Denver, Colorado. The spill was neutralized with sodium carbonate. 2 HNO3(aq) + Na2CO3(s) 2 NaNO3(aq) + H2O(l) + CO2(g) (a) Calculate H° for this reaction. kJ

asked on November 26, 2007
27. dr. bob

Use the data in Table 5.4 to calculate the partial pressure of He in dry air assuming that the total pressure is 1.0 atm. Assuming a temperature of 21°C, calculate the number of He atoms per cubic centimeter. atoms/cm3 .00000524 - atmospheric composition

asked on November 17, 2007
28. chemistry

hot-air balloon is filled with air at a volume of 3.64 x 10^3 m^3 at 745 torr at 39C. the air in balloon is heated to 60C, causing balloon to expand to a volume of 4.50x 10^3 m^3. what is the ratio of the number of moles of the air in heated balloon to

asked on November 15, 2007

Part of a roller-coaster ride involves coasting down an incline and entering a loop 30.0 m in diameter. For safety considerations, the roller coasters speed at the top of the loop must be such that the force of the seat on a rider is equal in magnitude to

asked on October 27, 2012
30. physics

A bag of sugar weighs 6.00 lb on Earth. What would it weigh in newtons on the Moon, where the free-fall acceleration is one-sixth that on Earth?

asked on February 17, 2010
31. FINANCE

Yield to call Six years ago, the Singleton Company issued 20-year bonds with a 14 percent annual coupon rate at their \$1,000 par value. The bonds had a 9 percent call premium, with 5 years of call protection. Today, Singleton called the bonds. Compute the

asked on September 18, 2007
32. chem

The units of parts per million (ppm) and parts per billion (ppb) are commonly used by environmental chemists. In general, 1 ppm means 1 part of solute for every 106 (one million) parts of solution. Mathematically by mass: ppm = µg solute / g solution = mg

asked on November 3, 2007
33. chem

I have the following problems- write net ionic equations for reactions if no reaction write NR.... silver nitrate and ammonium carbonate sodium phosphate and potassium nitrate silver nitrate and barium chloride copper (II) chloride and sodium hydroxide

asked on November 2, 2007
34. Calculus

The position function of a particle in rectilinear motion is given by s(t) = 2t^3 – 21t^2 + 60t + 3 for t ≥ 0. Find the position and acceleration of the particle at the instant the when the particle reverses direction. Include units in your answer.

asked on January 8, 2016
35. chemistry

water vapor and nitrogen dioxide gas NO2 are cimbined to manufacture ammonia. a by product of this reaction is oxygen gas. write a balanced equation for this reaction. i do not understand this at all please help me figure it out

asked on April 16, 2009
36. math

By what fraction would you multiply 8 1/2 so that the product is about 5? Plesae explain.

asked on January 25, 2015
37. CALCULUS

a man weighiing 7-kg lies in a hammock whose ropes make angles of 20 and 25 degrees with the horizontal. What is the tension in each rope?

asked on February 17, 2008
38. Chemistry

Consider the following unbalanced equation. H1+(aq) + Fe(s) H2(g) + Fe2+(aq) What is the balanced oxidation half-reaction? What is the balanced reduction half-reaction? What is the balanced overall cell reaction?

asked on June 8, 2012
39. chem

In 1897 the Swedish explorer Andree tried to reach the North Pole in a balloon. The balloon was filled with hydrogen gas. The hydrogen gas was prepared from iron splints and diluted sulfuric acid. The reaction is given below. Fe(s) + H2SO4(aq) FeSO4(aq) +

asked on November 16, 2007
40. Calculus

Find the x-coordinates of any relative extrema and inflection point(s) for the function f(x) = 3x^(1/3) + 6x^(4/3). Please use an analysis of f ′(x) and f ′′(x).

asked on January 8, 2016
41. Check my answers?

The passage: For decades, America has been locked in hostile confrontation with the two great Communist powers, the Soviet Union and the People’s Republic of China. We were engaged with the one at many points and almost totally isolated from the other,

asked on August 30, 2014
42. FINANCE

Current yield and yield to maturity A bond has a \$1,000 par value, 10 years to maturity, a 7 percent annual coupon, and sells for \$985. a. What is its current yield? b. What is its yield to maturity (YTM)? c. Assume that the yield to maturity remains

asked on September 18, 2007
43. Finance

Interest rate premiums A 5-year Treasury bond has a 5.2 percent yield. A 10-year Treasury bond yields 6.4 percent, and a 10-year corporate bond yields 8.4 percent. The market expects that inflation will average 2.5 percent over the next 10 years (IP10 _

asked on September 15, 2007
44. Physics

A 60 cm long wire is oriented from east to west directly above the equator and carries a current of 5 A (toward the east). What is the magnitude and direction of the magnetic force on this wire due to the earth’s magnetic field (30 µT oriented south and

asked on July 24, 2019

A tennis ball of mass= 0.058 kg and speed= 19 m/s strikes a wall at a 45 degree angle and rebounds with the same speed at 45 degrees. What is the magnitude of the impulse given to the ball?

asked on November 20, 2011
46. stats

I need help. I am so so lost and need the answers and step by step if possible. I have tried everything but I think I'm just.. having a huge brainfart. I need the answers and the step by step please A quiz consists of 8 multiple choice questions, each with

asked on August 5, 2019
47. Quick calc question

If f(x) and g(x) are continuous on [a, b], which one of the following statements is false? the integral from a to b of the sum of f of x and g of x, dx equals the integral from a to b of f of x, dx plus the integral from a to b of g of x dx the integral

asked on February 12, 2016
48. MATH

Tara says that 1/2 of a salad is always the same amount. Lynn says that it could be different amounts, depending on how large the salad is. Who is correct? Why?

asked on January 25, 2010
49. Physics

A person walks the path shown below. The total trip consists of four straight-line paths. Path 1 is 30.0 m due east. Path 2 is 200.0 m due south. Path 3 is 140.0 m 30.0° south of west. Path 4 is 170.0 m 60.0° north of west. At the end of the walk, what

asked on November 1, 2012
50. Math

Topic: Water Footprint. City of New York 2011 rate of 7.64/100 cubic feet of water. Calculate the cost of each of the following based on this rate. Use the conversion factor of 7.48 gallons per cubic food. A. A standard washing machine uses approximately

asked on April 24, 2017
51. Quick calc question

Determine the interval on which f(x) = ln(x) is integrable. (0, ∞) [0, ∞) (−∞, 0) U (0, ∞) All reals

asked on February 16, 2016
52. chem

2 HCl(aq) + Ba(OH)2(aq) BaCl2(aq) + 2 H2O(l) H = -118 kJ Calculate the heat when 112.4 mL of 0.500 M HCl is mixed with 300.0 mL of 0.515 M Ba(OH)2. Assuming that the temperature of both solutions was initially 25.0°C and that the final mixture has a mass

asked on December 1, 2007
53. algebra

A small garden measures 14 ft by 6 ft. A uniform border around the garden increases the total area to 209 ft2. What is the width of the border?

asked on January 24, 2016
54. chem

The specific heat capacity of silver is 0.24 J/°C·g. (a) Calculate the energy required to raise the temperature of 140.0 g Ag from 273 K to 295 K. J (b) Calculate the energy required to raise the temperature of 1.0 mol Ag by 1.0°C (called the molar heat

asked on November 26, 2007
55. chemistry

0.60 g of hydrogen chloride (HCl) is dissolved in water to make 6.5 L of solution. What is the pH of the resulting hydrochloric acid solution?

asked on March 31, 2011
56. Chemistry

My chemistry is bad. I know these are very easy but I cannot solve them . 1. a) Prepare 200 ml of 2 M HCl solution from stock bottle containing 37% w/w HCl and d = 1.2 (g/ml). MWHCl = 36.5 g b) Calculate M of 37% w/w HCl solution? d= 1.2, then solve the

asked on December 4, 2014
57. chem

calculate the change in energy expected for each of the following processes 1. Rb(g) + Br(g) --> Rb+ (g) + Br- (g) 2. Mg(g) + I(g) --> Mg+ (g) + I- (g) 3. Mg+ (g) + I(g) -> Mg+2 (g) + I- (g) 4. Mg(g) + 2I (g) -> Mg+2 (g) + 2I- (g) in kJ

asked on December 6, 2007
58. Social studies

Compare the experience of farmers,coal miners,and union labores during the 1920s. What did many have in common? 1.Economic prosperity 2. Public disapproval 3. Federal assistance 4. Financial hardship I choose A is it correct Ms. Sue

asked on March 3, 2017
59. chem

consider separate 1Lsamples of He and UF6 both at 1 atm and containing the same number of moles. what ratio of temps for the two samples would produce the same root mean square velocity?

asked on November 16, 2007
60. Math

A custodian pours1/8 gallon of cleaning solution into each pail of water that she uses. how many pails of water and cleaning solution can the custodian make using 16 gallons of cleaning solution?

asked on March 25, 2015
61. Math

Suppose a person were to breath an average of 16 times per minute. How many years would it take for them to breath one billion times? Assume there are 365 days in one year. Round your answer to the nearest single year.

asked on April 24, 2017
62. chem

75L stainless steel container was charged with 3 atm of hydrogen gas and 4 atm of oxygen gas. a spark ignited the misture, producing water. what is the pressure of the tank at 25C? at 125C?

asked on November 16, 2007
63. chemistry

In a dry cell, MnO2 occurs in a semisolid electrolyte paste and is reduced at the cathode. The MnO2 used in dry cells can itself be produced by an electrochemical process of which one half-reaction is shown below. Mn2+(aq) + 2 H2O(l) MnO2(s) + 4 H+(aq) + 2

asked on May 5, 2015
64. algebra

If f(x)=x+7 and g(x)=1/x-13, what is the domain of (f x g)(x)? Please explain.

asked on April 10, 2019
65. science

Mountains produced by tensional stress, like the Teton Range in Wyoming, are called

asked on June 2, 2012
66. physics

A physics student pulls a block of mass m = 23 kg up an incline at a slow constant velocity for a distance of d = 4 m. The incline makes an angle q = 25° with the horizontal. The coefficient of kinetic friction between the block and the inclined plane is

asked on March 11, 2012
67. Quick calc question

Write the Riemann sum to find the area under the graph of the function f(x) = x2 from x = 1 to x = 5. 1. the summation from i equals 1 to n of the product of the quantity squared of 1 plus 5 times i over n and 4 over n 2. the limit as n goes to infinity of

asked on February 12, 2016
68. Physics

A boy sledding down a hill accelerates at 1.65 m/s2. If he started from rest, in what distance would he reach a speed of 7.30 m/s?

asked on October 3, 2012
69. physics

if two lightning bolts hit exactly the same place, act exactly the same time in one frame of reference, is it possible that observers in other freames will see the bolts hitting at different times or at the different places? explain.

asked on September 22, 2011
70. chem

A 75.0 L stainless steel container was charged with 3.00 atm of hydrogen gas and 4.00 atm of oxygen gas. A spark ignited the mixture, producing water. What is the pressure in the tank at 25°C? in atm What is the pressure in the tank at 125°C? in atm

asked on November 17, 2007
71. phsyics

the coefficient of volume expansion for iron is 3.6 X 10^-5/C degrees. If a 17 m long rod of iron is cooled from 100 degrees C to 5 degrees C, What is the new length?

asked on March 19, 2014
72. chemistry check

Dr.Bob you had told me to ignore 2x so I wondering if I wrote my did these steps correctly. Calculate the molar solubility of nickel (II) hydroxide in 0.100 M sodium hydroxide The solubility product of nickel (II) hydroxide at 25°C is 1.6 x 10-16. Ni(OH)2

asked on May 17, 2007
73. math stats

When 100 students at UCF were given a calculus problem that required the use of integration by parts, 95 were able to solve it. When 100 FAU students were given the same problem, 68 were able to solve it. What is the test statistic associated with the

asked on August 5, 2019
74. Quick calc question

Determine the interval on which f(x) = ln(x) is integrable. (0, ∞) [0, ∞) (−∞, 0) U (0, ∞) All reals

asked on February 12, 2016
75. Math

Can someone get the math for the worksheet? I'm havibg troubles getting the answers and how to get them. Thxs!

asked on March 7, 2019
76. chem

Consider the following cyclic process carried out in two steps on a gas. Step 1: 48 J of heat is added to the gas, and 20. J of expansion work is performed. Step 2: 70. J of heat is removed from the gas as the gas is compressed back to the initial state.

asked on December 2, 2007
77. FINANCE

Bond valuation Callaghan Motors’ bonds have 10 years remaining to maturity. Interest is paid annually; they have a \$1,000 par value; the coupon interest rate is 8 percent; and the yield to maturity is 9 percent. What is the bond’s current market price?

asked on September 18, 2007
78. science

How can i prepare a 100ml, 0.1M phosphate buffer solution (pH = 7) out of Na2HPO4 and NaH2PO4

asked on February 27, 2016
79. Quick calc question

Given that the antiderivative of f of x equals 1 divided by x is F(x) = Ln|x| + C, evaluate the integral from 1 to 2 of the 1 divided by x, dx. ln3 1/2 -1/2 ln2

asked on February 16, 2016
80. Physics

Two identical charges repel each other with a force of 10-5 N when they are 20 cm apart. a.) What is the force on each when they are 5 cm apart? b.) When they are 100 cm apart?

asked on February 12, 2016
81. Quick calc question

Find the x-coordinates where f '(x) = 0 for f(x) = 2x + sin(4x) in the interval [0, π].

asked on January 29, 2016
82. Chemistry

A student constructs a galvanic cell that has a strip of lead metal immersed in a solution of 0.1M Pb(NO3)2 as one half-cell and a strip of zinc metal immersed in a solution of 0.1M Zn(NO3)2 as the other half-cell. The measured cell potential is less than

asked on March 30, 2010
83. chem

2 HNO3(aq) + Na2CO3(s) 2 NaNO3(aq) + H2O(l) + CO2(g) (a) Calculate H° for this reaction. kJ

asked on November 26, 2007
84. Algebra

How to write |y|-2=0 in standard form?

asked on February 12, 2017
85. psychology

Rind, B., & Strohmetz, D. (1999). Effect on restaurant tipping of a helpful message written on the back of customers’ checks. Journal of Applied Psychology, 29, 139-144. doi:10.1111/j.15591816.1999.tb01378.x This is the article to use to answer these

asked on July 6, 2014
86. physics

A pitcher throws a baseball horizontally from the mound to home plate. The ball falls 0.955 m (3.13 ft) by the time it reaches home plate 18.3 m (60 ft) away. How fast was the pitcher's pitch?

asked on November 18, 2012
87. physics

Stemming a chimney. A rock climber of mass 71 kg wants to make her way up the crack between two rocks as shown in the figure below. The coefficient of friction between her shoes and the rock surface is ìS = 0.90. What is smallest normal force that she can

asked on October 6, 2011
88. english

Is this a good thesis statement for an essay titled "dress codes in schools"? If not, could you please help in reconstructing as it is for a final paper? Thanks While there may be opposition from students and parents, dress codes should be enforced in

asked on May 26, 2008
89. chem

A balloon filled with 22.3 mol helium has a volume of 500. L at 0.0°C and 1.00 atm pressure. The temperature of the balloon is increased to 38.0°C as it expands to a volume of 570. L, the pressure remaining constant. Calculate q, w, and E for the helium

asked on November 26, 2007
90. Language Arts

what is the participle or participial phrase in the following sentence: The art students, brought by bus, toured the museum.

asked on March 29, 2016
91. Chemistry

How would you prepare 2.5 L of a 0.05 M solution of iron (III) chloride using iron (III) chloride hexahydrate Since 1 mol iron(III)chloride hexahydrate contains 1 mol iron(III) chloride, use the molar mass of the hexahydrate. M x L = grams/molar mass Solve

asked on May 2, 2007
92. chemistry

What is the molarity of the Cl- ion in the solution of a sample containing 0.187g Cl- dissolved in 50.0 ml water?

asked on October 23, 2007
93. FINANCE

Bond valuation Nungesser Corporation’s outstanding bonds have a \$1,000 par value, a 9 percent semiannual coupon, 8 years to maturity, and an 8.5 percent YTM. What is the bond’s price?

asked on September 18, 2007
94. Chemistry

What is the chemistry behind the ASA – FeCl3 reaction?

asked on May 2, 2007
95. Fine Arts

The question asks, What are some of the similarities and differences between scroll paintings in China and Japan. I have the similarities down, but i cant find any differences. Help?

asked on May 6, 2012
96. Diffraction

Question Details: A row of seats is parallel to a stage at a distance of 8.70 m from it. At the center and front of the stage is a diffraction horn loudspeaker that has a width of 7.50 cm. The speaker is playing a tone at a frequency of 9300 Hz . The speed

asked on December 2, 2008
97. chem

A balloon filled with 22.3 mol helium has a volume of 500. L at 0.0°C and 1.00 atm pressure. The temperature of the balloon is increased to 38.0°C as it expands to a volume of 570. L, the pressure remaining constant. Calculate q, w, and E for the helium

asked on November 26, 2007
98. Science

A coach wants to find out the speed of the runners on the track team.Tell what simple equipment the coach need in order to do this and explain how it should be done.

asked on January 21, 2018
99. math

Charlie wants to buy a \$900 TV in 9 months. How much should he invest now at 17% simple interest to have the money in 9 months?

asked on January 28, 2009
100. chem

A spherical glass container of unknown volume contains helium gas at 25°C and 1.950 atm. When a portion of the helium is withdrawn and adjusted to 1.00 atm at 23°C, it is found to have a volume of 1.55 cm3. The gas remaining in the first container shows

asked on November 17, 2007

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