Sara

Most popular questions and responses by Sara
1. Physics

Multiple Concept Example 9 provides background pertinent to this problem. The magnitudes of the four displacement vectors shown in the drawing are A = 16.0 m, B = 12.0 m, C = 13.0 m, and D = 23.0 m. Determine the (a) magnitude and (b) direction for the

asked on May 29, 2012
2. math

Find dy/dx and d2y/dx2. x = et, y = te−t

asked on July 28, 2014
3. Algebra

What is the solution to 5-t=23? My answer is 18. What is the value of b if -7+b=-8? My answer is -1. What is the solution to 5q=-75? My answer is either -25 or -15. What is the solution to -6z=72? My answer is -12. What is the solution to -7+h=12? My

asked on September 15, 2015
4. MACROECONOMICS

Which of the problems in the construction of the CPI might be illustrated by each of the following situations? Explain. a. the invention of the Sony Walkman b. the introduction of air bags in cars c. increased personal computer purchases in response to a

asked on April 12, 2009
5. statistics

the probability that a house in an urban area will develop a leak is 5%. if 23 houses are randomly selected, what is the probability that none of the houses will develop a leak?

asked on April 28, 2013
6. chem

Which of the following elements would you expect to gain electrons in chemical changes? (Select all that apply.) gold chromium zirconium nitrogen iodine

asked on September 21, 2010
7. math

Two cars are side by side. One is 3.9 meters long. The other is 6% shorter. How long is the second car? I know the answer is 3.7, but how?

asked on June 25, 2018
8. Chemistry

Given the thermodynamic data in the table below, calculate the equilibrium constant for the reaction: 2SO2(g)+O2--> 2SO3 Substance (DeltaH^o) (Delat S^o) SO2 -297 249 O2 0 205 SO3 -395 256 Answer (it was given) 2.32x10^24 Even though the answer is given

asked on March 16, 2008
9. Chemistry

Restart the PhET simulation and set it up in the following manner: select Oscillate, select No End, and use the parameters in parentheses by sliding the bars for Amplitude (1.00 cm), Frequency (1.20 Hz ), Damping (none), and tension (highest). Using the

asked on October 18, 2018
10. English

Story : The Ethanol Debate Natalie Stewart What feature of the selection BEST illustrates that it is a persuasive essay? A) < -- A? the chart showing the rise in corn prices B) the information on how farmers feed their herds C) the description of how

asked on May 11, 2015
11. How many milliliters of a stock solution of 6.00 M

How many milliliters of a stock solution of 6.00 M HNO3 would you have to use to prepare 0.190 L of 0.490 M HNO3? I used the equation M1V1=M2V2 6M*V1 = 0.190L*0.490 M lead me to this V1=0.190L*0.490M/6.00 M =0.0931 L per M/6.00M =0.0155166L

asked on August 28, 2015
12. math help

Round to nearest ten thousandth: 4.803621

asked on January 22, 2014
13. chemistry

Using your answer from Part A, calculate the volume of a mole of Na atoms (in cm3/mol ). Assume that the entire volume is occupied by Na atoms leaving no gaps or holes between adjacent atoms. (Answer A is V= 2.70*10^7)

asked on November 10, 2008
14. chemistry

When the conductivity is at a minimum, what must be true about the amount of Ba(OH)2 compared to H2SO4? The Ba(OH)2 dissociates as Ba+2 + 2 OH-. H2SO4 dissociates as 2 H+ + SO4-2. Why does it not conduct at this low point? Why does it conduct more before

asked on July 25, 2012
15. chemistry

Based upon the intermolecular forces present, rank the following substances according to the expected boiling point for the substance: MgF2, H2O, HCl, N2

asked on April 3, 2014
16. Chemistry

Diethyl ether has a boiling point of 34.5C, and 1-butanol has a boiling point of 117C. Both of these compounds have the same numbers and types of atoms. Explain the difference in their boiling points. The answer I found was that: only 1-butanol can form

asked on December 6, 2010

Jen purchased a condo in Naples Florida for \$699,000. She put 20% down and financed the rest at 5% for 35years. What are Jens total finance charge?

asked on April 12, 2015
18. math

The value of Sara's new car decreases at a rate of 8% each year. 1.Write an exponential function to model the decrease in the car's value each month. 2.Write an exponential function to model the decrease in the car's value each week. 3.Write an exponential

asked on November 17, 2017
19. Science-Enr. Phys.

A box of books weighing 325 N moves at a constant velocity across the floor when the box is pushed with a force of 425 N exerted downward at an angle of 35.2 degrees below the horizontal. Fink Mu,k between the box and the floor. There have been several of

asked on February 25, 2007
20. Check my answers

Question 1.Choose the answer that identifies the case of the parentheses word. My grandparents always go to the square dances with the Warrens and (them). nominative objective possessive *** my answer none of the above Question 2. Choose the pronoun that

asked on October 15, 2014
21. math

The formula of a trapezoid is A=1/2h(b1+b2) Express b1 in terms of A,h,and b2 I did A=1/2hb1+1/2hb2 A=hb1/2 +hb2/2 A-hb2(2/h)=hb1/2(2/h) A-b2=b1 I am not sure if this is correct? I was confused on how to do this. Any help or explanation is greatly

asked on October 4, 2016
22. Math

Sarah secured a bank loan of \$200,000 for the purchase of a house. The mortgage is to be amortized through monthly payments for a term of 15 yr, with interest rate of 6%/year compounded monthly on the unpaid balance. She plans to sell her house in 5 yr.

asked on May 15, 2012
23. physics

Three identical thin rods, each of length L and mass m, are welded perpendicular to one another as shown below. The assembly is rotated about an axis that passes through the end of one rod and is parallel to another. Determine the moment of inertia of this

asked on November 6, 2008
24. anatomy

if you wanted to flex your arm, and both your biceps and triceps contracted simultaneously, what would happen? and where is most of the muscle weight found in humans?

asked on October 28, 2007
25. DrBobb222 : Chemistry HElp...Please Check

Standardization of the Sodium Thiosulfate Solution Make up a standard solution of potassium iodate by accurately “weighing by difference” about 0.1 g of KIO3 and placing it in your 100 mL volumetric flask. Fill the flask to mark with distilled water.

asked on October 21, 2008
26. chemistry

In the reaction between CV+ and –OH, one species is acting as the Lewis base, the other as the Lewis acid. (Note: A Lewis acid is not necessarily a proton donor. It is, however, always an electron pair acceptor). Which reagent is the Lewis acid? A. CV+

asked on July 13, 2010
27. English

In the following sentence, identify the part of speech of the italicized word. Thousands of years ago, fish were caught in nets and traps. A. Verb B. Preposition C. Pronoun D. Conjunction Is it B?

asked on August 16, 2012
28. Percentage

A flat-screen TV costs \$1,400. The TV is on sale for 35% off. What's the discount price?

asked on January 4, 2017

Andres Michael bought a new boat. He took out a loan for \$23,980 at 3.75% interest for 4 years. He made a \$4,470 partial payment at 4 months and another partial payment of \$3,180 at 9 months. How much is due at maturity?

asked on October 10, 2014
30. calculus

A street light is mounted at the top of a 6-meter-tall pole. A man 2 m tall walks away from the pole with a speed of 1.4 m/s along a straight path. How fast is the tip of his shadow moving when he is 16 m from the pole?

asked on October 16, 2012
31. Music

Which term names a musical parameter? tempo notation

asked on October 6, 2015
32. math

write each addiction vertically. decide which new groups you will make. then add to see if you were correct. 256+1.273 A new ten? A new hundred? A new thousand?

asked on October 1, 2013
33. AP Chemistry

A 5.0 M solution of HNO3 is titrated with 0.3 M NaOH. Identify the species that have the highest concenttrations in the solution being titrated halfway to the equivalence point. A 25.15 ml of 0.35 m HNO3 was titrated with an unknown concentration of NaOH.

asked on March 29, 2015
34. Chemistry

Calculate the molarity and the molality of an NH3 solution made up of 30 g of NH3 in 70 g of water. The density of the solution is 0.982 g/ml. Molar Mass of NH3 = 17.04 g

asked on December 2, 2010
35. Chemistry

Dinitrogen pentoxide, N2O5, decomposes by first-order kinetics with a rate constant of 0.15 s-1 at 353 K. (a) What is the half-life (in seconds) for the decomposition of N2O5 at 353 K? (b) If [N2O5]0 = 0.0579 mol·L-1, what will be the concentration of

asked on June 28, 2013
36. Maths

50 divided into two parts such that if 6 is subtracted from one part , 12 is added to the second part we get same number .

asked on December 2, 2016
37. Chemistry

The solubility of CO2 in water at 25 degrees C and 1 atm is 0.034 mol/L. What is its solubility under atmospheric conditions? (The partial pressure of CO2 in air is 0.0003 atm.) Assume that CO2 obeys Henry's law. My Answer: 1.02 x 10^-5 mol/L

asked on December 2, 2010
38. Physics

Three astronauts, propelled by jet backpacks, push and guide a 118 kg asteroid toward a processing dock, exerting the forces shown in the figure, with F1 = 32 N, F2 = 56 N, F3 = 38 N, θ1 = 30°, and θ3 = 60°. What is the (a) magnitude and (b) angle

asked on March 31, 2016
39. Mendelian Genetics

Assume you are performing a cross between a plant that is heterozygous for the dominant traits red flowers and wrinkled seeds, with a plant that is homozygous for the recessive traits white flowers and smooth seeds. Assume the alleles are R for red

asked on January 20, 2015
40. physics

a roller coaster moves 85m horizonally, then travels 45m at an angle of 30 degrees above the horizontal. what is its displacement from its starting point?

asked on October 29, 2008
41. Math

One of the sides of a parallelogram is 4.2 cm and the altitude to that side is 3.6 cm. Find the perimeter of the parallelogram if the altitude to the other side is 2.4 cm.

asked on February 23, 2017
42. chemistry

Calculate the mass of oxygen gas required to occupy a volume of 6 L at a pressure of 20.9 kPa and a temperature of 37◦C.

asked on April 30, 2015
43. Chemistry

About 13% of the acid in a 0.10M solution of a weak acid dissociates to form ions. What is the H3O+ concentration? What is the OH- concentration? What is the pH of the solution?

asked on July 18, 2012
44. physics

If 335 g of water at 65.5 °C loses 9750 J of heat, what is the final temperature of the water? Liquid water has a specific heat of 4.18 J/(g.°C). °C (Answer a number only, no units. Round to the tenth place). This is an example of an endothermic or

asked on May 22, 2017
45. Chemistry

From the equation below, how many grams of barium sulfate can be produced from 20.8 g of barium chloride? BaCl2 + Na2SO4 -> BaSO4 + 2NaCl

asked on May 19, 2015
46. precalculus

an airplane flying at 550 miles per hour has a bearing of N 52(DEGREES)E. After flying 1.5 hours, how far north and how far east has the plane traveled from its point of departure?

asked on March 11, 2010

H2(g) + CO2(g) H20(g) + CO(g) When H2(g) is mixed with CO2(g) at 2,000K, equilibrium is achieved according to the equation above. In one experiment, the following equilibrium concentrations were measured: [H2]=0.20 M [CO2]=0.30 M [H2O]=[CO]=0.55M a) What

asked on February 25, 2007
48. chemistry 30a

What volume (in mL) of an 8% w/v acetic acid solution would be needed to form 2.2 L of carbon dioxide gas at 25.2 degrees Celsius and 0.9982 atm? Assume the acid is reacted with excess sodium bicarbonate, and round your final answer to two sig figs.

asked on March 12, 2012
49. finance

Jiminy's Cricket Farm issued a 30-year, 7.2 percent semiannual bond 9 years ago. The bond currently sells for 85.5 percent of its face value. The book value of this debt issue is \$107 million. In addition, the company has a second debt issue, a zero coupon

asked on May 9, 2016
50. chemestry

consider the reaction 2N2O(g) == O2(g)+2N2(g).which of the following will cause a shift in the equilibrium to the left?

asked on November 1, 2014
51. Physics - Mechanics and Ocsillatory Motion

The force shown in the figure acts on a 1.7-kg object whose initial speed is 0.44 m/s and initial position is x = 0.27 m. the figure can be found at: [[webassign dot net forwardslash walker forwardslash 07-16 dot gif]] (a) Find the speed of the object when

asked on October 30, 2010
52. English-Writeacher

Recently my class and I read a short story called "A l is Calm." It is basically about this girl named Katherine and her grandma who is suffering from the Alzheimer's disease. It starts out as this: Katherine's grandma has to be taken to the doctor because

asked on October 5, 2010
53. Physics

Suppose your car was mired deeply in the mud and you wanted to use the method illustrated in the figure to pull it out. (a) What force in newtons would you have to exert perpendicular to the center of a rope to produce a force of 10,000 N on the car if the

asked on November 7, 2016
54. MATH

You wish to mentally estimate the total cost of items that have the following prices: \$1.85, \$.98, \$3.49, \$9.78, and \$6.18. Rounding off the items to the nearest half-dollar, your estimate of the total cost of these items is A. \$22.50. B. \$22.30. C.

asked on August 18, 2012
55. Linear algebra

Let L1 be the line passing through the point P1=(−1, −1, 8) with direction vector →d1=[1, 0, −3], and let L2 be the line passing through the point P2=(7, −11, 14) with direction vector →d2=[1, 2, −3]. Find the shortest distance d between

asked on March 18, 2017
56. physics

A ball of mass 0.075 kg is fired horizontally into a ballistic pendulum. The pendulum mass is 0.350 kg. The ball is caught in the pendulum, and the centerof mass of the system rises a vertical distance of 0.145 m in the earth's gravitational field. What

asked on March 28, 2010
57. Physics

A car is traveling along a straight road at a velocity of +31.0 m/s when its engine cuts out. For the next ten seconds, the car slows down further, and its average acceleration is a1. For the next five seconds, the car slows down further, and its average

asked on November 30, 2008
58. Empires

I need help to compare and contrast the Babylonian and Hittite empires

asked on September 22, 2014
59. Chemstry

I just copied this because i have a couple more questions on this part.... Sulfuric acid/ Lead Battery: -the electrodes for the battery are composed of Pb(s), PbO2, and/or PbSO4. What are the half reaction occuring at each electrode? include electrolysis

asked on April 28, 2008
60. English

The speaker in “I, Too, Sing America” survives adversity because he feels faith that he will one day be affirmed by white America. he has uncovered the hypocrisy around him. he is better than the people who are oppressing him. hope that he can one day

asked on February 6, 2012
61. Algebra

can somebody please help me with this question I've spent more than 3 hours on this, still nothing Let L1 be the line passing through the point P1=(2, −4, −6) with direction vector →d1=[1, 0, 2]T, and let L2 be the line passing through the point

asked on March 18, 2017
62. English-Poetry

My Guilt When I was a child I walked two miles to school accompanied by a neighbor boy two years younger. Freddie was fat and freckle faced with wheat-straw hair and a mean stepmother. It was late fall and one day his father bought him a new winter cap. It

asked on April 21, 2010
63. math

A movie theater seats 500 people. For any particular show, the amount of money the theater makes is a function m(n) of the number of people, n, in attendance. If a ticket costs 2 dollars, find the domain and range of this function. domain: ?≤ n ≤?

asked on September 3, 2011
64. History

what are two themes that would be appropriate for thematic time lines of important events from prehistory to A.D.1600.

asked on January 18, 2015

Explain the process that takes place in the stroma including and reactants going in nd the products produced from these processes in a. bright sunlight and in b. darkness. c. what happens over an extended period of darkness of many days? What I need to

asked on November 21, 2016
66. Sixth Grade Simplest Form

Im having a hard time trying to solve this problem. Can someone please help me? Marcial found a recipe for fruit salad that he wanted to try to make for his birthday party. He decided to triple the recipe. 3 1/2 cups thinly sliced rhubarb 15 seedless

asked on September 16, 2014
67. chemistry

Aqueous sodium sulfate reacts with aqueous barium chloride to produce solid barium sulfate and aqueous sodium chloride. the solution contains 3.44g of barium chloride. you have a 0.282M solution of sodium sulfate. determine the volume of the sodium sulfate

asked on April 17, 2016
68. Socials-Ms. Sue

Explain the relationship between mercantilism and colonialism. Can there ever be a profit without one party being short-changed? Explain. Mercantilism was the belief that colonies existed to enrich the mother country. Ms. Sue I am having trouble on this

asked on January 17, 2010
69. Chemistry

Just having some trouble with this chemistry problem.. Thanks for help! Toxic carbon monoxide (CO) gas is produced when fossil fuels such as petroleum burn without enough oxygen. The CO can eventually be converted to CO2 in the atmosphere. Automobile

asked on January 15, 2013
70. Science

Which of the following statements is true about Earth's magnetic poles? A.They are located at earths geographic poles B.They are the areas where Earths magnetic field is weakest. C. They are the areas where Earths magneic field is strongest. D. Earth has

asked on April 27, 2016
71. English-Friendship Poem

What are Friends For-by rosellen brown What are friends for, my mother asks. A duty undone, visit missed, casserole unbaked for sick Jane. Someone has just made her bitter. Nothing. They are for nothing, friends, I think. All they do in the end-they touch

asked on April 7, 2010
72. geography/social studies

PLEASE HELP ME if you were an entrepreneur, which european country might be the best place to start your new business? explain your reasoning

asked on May 3, 2016
73. Chemistry

Using household bleach and saltwater of the same molarity, describe the quantities of each that would me needed to make 30 ml of a solution that contained 50% of the hypochlorite in household bleach.

asked on February 22, 2015
74. Chemistry

Prepare M/20 oxalic acid solution.Using this solution, find molarity, strength, and percentage purity of the sodium hydroxide solution.

asked on June 13, 2016
75. math

How many gram ofsodiun fluoride should be added to 100000liter of drinking water containing 0.6 ppm of sodium fluoride to provide a recommended concentration of 1.75 ppm

asked on June 23, 2014
76. Math

When a class took a math test, 15% of the class failed, 25% made some mistakes (but didn’t fail), and 24 students got perfect scores. How many students were in the class?

asked on February 23, 2017
77. math

what is the largest negative coterminal angle of -417?

asked on August 16, 2011
78. chemistry

suppose you heat a hydrate too quickly and some of it was lost as it spattered out of the container. Explain how this would affect the calculated percent of mass and the chmical formula

asked on November 18, 2009
79. Square Roots

Between what two consecutive integers does the square root of 124 lie? 11 and 12 12 and 13 13 and 14 14 and 15

asked on November 11, 2014
80. social studies

how did the spanish conquest affect native americans and africans?

asked on March 31, 2008
81. English

1. Choose the answer that best matches the word in italics. Samantha tried to look IMPASSIVE when they announced her essay as a finalist in the competition.  (1 point) surprised unemotional*** unsure vibrant 2.   Choose the answer that best matches the

asked on September 29, 2016
82. physics

A 48-kg girl stands on a 8-kg wagon holding two 19.5-kg weights. She throws the weights horizontally off the back of the wagon at a speed of 9.0 m/s relative to herself. Assuming that the wagon was at rest initially, what is the speed with which the girl

asked on December 5, 2015
83. Maths

divide 1000 among a,b,c in such a way that a gets 120 more than b and b gets rs 110 more than c .hw much each get

asked on December 4, 2016
84. Chemistry

The complex [Co(ox)3]4- has a high-spin electron configuration. How many unpaired electrons are there in the complex? I know because it's a high-spin, it's tetrahydral shaped. But I don't know what (ox) is so, I'm stuck in finding the oxidation state of Co

asked on July 26, 2013

Lead metal is added to 0.150 M Cr3+(aq). Pb(s)+2Cr3+(aq)⇌Pb2+(aq)+2Cr2+(aq). KC=3.2×10−10 What is [Pb2+] when equilibrium is established in the reaction? What is [Cr2+] when equilibrium is established in the reaction? What is [Cr3+] when equilibrium

asked on February 17, 2017
86. Calculus

Calculate the height of a cylinder of maximum volume that can be cut from a cone of height 20 cm and base radius 80 cm , please help me

asked on December 25, 2011
87. chemistry

At a pressure of 405 kPa, the volume of a gas is 6.00 cm3. Assuming the temperature remains constant, at what pressure will the new volume be 4.00 cm3?

asked on February 24, 2011
88. Physics

A light ray of wavelength 610 nm is incident at an angle θ on the top surface of a block of polystyrene surrounded by water. Find the maximum value of θ for which the refracted ray will undergo total internal re- ﬂection at the left vertical face of

asked on January 25, 2011
89. Chemistry

Balance TeO3^3- + N2O4 --> Te +NO3^- using oxidation numbers

asked on June 15, 2015
90. Science

What are neap tides, and why do they occur? Neap tides are the weaker tides. They occur when the sun and the moon are perpendicular to each other with respect to earth. Please correct me if I'm wrong, thanks

asked on February 10, 2010
91. AP Human Geography

1. What role does migration play in the geographic pattern? 2. How about interaction & isolation after migration takes place? 3. When do dialects begin to become so different that they may be viewed as a different language? 4. How has the Internet

asked on November 18, 2015
92. Science

Which of the following shows three elements in order of increasing conductivity? Ge, O, Mn O, Ge, Mn Mn, O, Ge Mn, Ge, O

asked on November 17, 2015
93. econ

The terms below are measures or individual components of the money supply. Specifically considering the money supply of the United States, rank these items from largest to smallest in terms of dollar value. Currency, M2,M1,Balances in savings accounts,

asked on March 27, 2014
94. Calculus

A right circular cylinder is changing shape. The radius is decreasing at the rate of 2 inches/second while its height is increasing at the rate of 5 inches/second. When the radius is 4 inches and the height is 6 inches, how fast is the a) volume changing

asked on November 2, 2014
95. Chemistry

Which of the following procedures involves a physical change in one of the substances? separating an oil from solution by cooling it

asked on October 13, 2015

If there had not been a system of military alliances in place in Europe in 1914, would the assassination of Archduke Franz Ferdinand have resulted in World War I?

asked on May 13, 2015
97. Eng

What is the interpretation of the journey by Duane big eagle

asked on July 1, 2014
98. Socials

factors which were responsible for the growing wealth and prosperity of England in the 17th century were: -defeat of Spanish Armada -building of colonies -trade with the colonies -agricultural revolution -technology -government please tell me if this is

asked on September 14, 2009
99. Chemistry

Dinitrogen pentoxide, N2O5, decomposes by a first-order reaction. What is the initial rate of decomposition of N2O5 when 3.6 g of N2O5 is confined in a 0.77 L container and heated to 65°C? For this reaction, k = 5.2 x 10^-3 s-1 in the rate law (for the

asked on June 28, 2013
100. chemistry

A 375 g sample of well water is found to contain 17.0 mg of lead. How much lead (in parts per million) is in the well water? Round to the nearest tenth. Don't forget the unit.

asked on June 12, 2012