# Questions Asked onSeptember 14, 2012

1. ## chemistry

calculate the lattice energy of sodium oxide (Na2O) from the following data: Ionization energy of Na(g): 495 kJ/mol Electron affinity of O2 for 2e: 603 kJ/mol Energy to vaporize Na(s): 109 kJ/mol O2(g) bond energy: 499 kJ/mol Energy change for the reaction

2. ## math

Find the slope m of the tangent to the curve y = 5/ sqrt (x) at the point where x = a > 0. what is the slope?

3. ## chemistry

At 23°C, Kp = 0.075 for the equilibrium: NH4HS (s) ↔ NH3 (g) + H2S (g) A sample of solid NH4HS is placed in a closed vessel and allowed to equilibrate. Calculate the equilibrium partial pressure (atm) of ammonia, assuming that some solid NH4HS remains.

4. ## economics

Suppose the price of widgets falls from $7 to$5 and consumption of widgets rises from 15 widgets a month to 25 widgets. Calculate your price elasticity of demand of widgets. What can you say about your price elasticity of demand of widgets? Is it Elastic,

5. ## Physics

14. A racing car accelerates uniformly through three gears, changes with the following average speed: 20 for 2.0 s 40 for 2.0 s 60 for 6.0 s What is the overall average speed of the car?

6. ## writing

Now that you've spotted the problems of shift of person and shift of number, revise the paragraph by removing these inconsistencies. Rewrite the paragraph, maintaining consistency by using first person plural when referring to the readers, and third person

7. ## Physics

A certain meter stick is calibrated in millimeters (the distance between two consecutive marks is ONE mm). A student measured the longest edge of a book and found that it was greater than 364 mm and less than 365 mm, but it was CLOSER to 365 mm than 364

8. ## chemistry

What is the mole ratio of benzene (C6H6) to n-octane in the vapor above a solution of 15.0% benzene and 85.0% n-octane by mass at 25 degrees Celcius? the vapor pressures of n-octane and benzene are 11 torr and 95 torr.

9. ## geometry

Algebra BD bisects

10. ## physical science

the 200g head of a golf club moves 40 m/s in a circular arc of 1.2m radius. How much force must the player exert on the handle of the club to prevent it from flying out of her hands at the bottom of the swing? ignore the mass of the clubs shaft.

48. ## Calculus

I'm supposed to find the limit as x approaches infinity of (2-x-sinx)/(x+cosx). I've thought about using the squeeze theorem, but I'm not sure it applies here. Can someone point me in the right direction? Thanks.

49. ## Biology

If you added .1 M NaOH to 1 M HCO2H a few millimeters at a time what would happen?

(-13) + (-1)

51. ## chmistry

Compound: Concentration: Measured deltaT LiCl 6.00 g/kg 0.492 deg C HCl 4.00 g/kg 0.389 deg C NaCl 6.00 g/kg 0.356 deg C Determine the value of the vant hoff factor for each salt for the experimentally measured delta T value. (kf=1.86) I have tried to

52. ## Physics

Runner A is initially 2.4 km west of a flagpole and is running with a constant velocity of 8.4 km/h due east. Runner B is initially 2.2 km east of the flagpole and is running with a constant velocity of 7.4 km/h due west. What will be the distance of the

53. ## college algebra

x y z rhs 1 1 2 3 2 1 6 3 0 3 4 13 i need to multiply some number and add to r3 answer quick!

54. ## Physics

Runner A is initially 2.4 km west of a flagpole and is running with a constant velocity of 8.4 km/h due east. Runner B is initially 2.2 km east of the flagpole and is running with a constant velocity of 7.4 km/h due west. What will be the distance of the

55. ## college algebra

x y z rhs 1 1 2 3 2 1 6 3 0 3 4 13 i need to multiply some number and add to r3 and get o in r3 answer quick!

56. ## Pre-Calculus need help in an Hour before test

y=f(x+5/2) I timesd x+5 by 2 to get rid of 2 at the bottom and timesd y by 2. Then to get rid of 2 from y i divided it, and i got this. y=1/2f(x+5) however my teacher got y=f(1/2(x+5)) what did i do wrong?

57. ## college algebra

x y z rhs 1 1 2 3 2 1 6 3 0 3 4 13 multiply some number by r2 and add result to r3(2) have to get o in r3 (1)- steps:------------------

58. ## • psychology

• Discussion of factors that enhance or impede information flow in each step of the process in the human memory model

59. ## math

find the average rate of change of F(x) on the intervals -1

60. ## physics

An object is dropped from a height H above the ground. This free-falling object requires 0.904 s to travel the last 34 m before hitting the ground. From what height H above the ground did the object fall? The acceleration of gravity is 9.8 m/s^2. Answer in

61. ## computer science

Which of the following is *not* a reason why a transmission signal might be corrupted or lost? 1. The protocol for the transmission is TCP/IP. 2. The cabling does not have any kind of shielding. 3. The copper used to connect the systems is contaminated. 4.

62. ## Health and Nutrition

What is protein?

63. ## Health and Nutrition

What is a complete protein?

64. ## Health and Nutrition

What is a vegetarian example of a complete protein?

65. ## Algebra..

f(x)= x^2+3 ; g(x)=3x-1 Check These Please? 1.(fg)(-1) = 5 2. (f o g)(1) =10 How would you solve this? 1. (g o f)(x)

66. ## physics

A lightbulb emits light that creates a shadow of a ball on a wall. If the radius of the ball is 12.1 cm, and the radius of the shadow is 25.5 cm, and the ball is 2.09 m away from the wall, how far is the lightbulb away from the wall?

67. ## Health and Nutrition

Describe risks associated with protein deficiency.

68. ## chemistry

A typical adult body contains 55 \% water. If a person has a mass of 61.0kg , how many pounds of water does she have in her body?

69. ## Health and Nutrition

Discuss risks (three or more) associated with consuming too much protein.

70. ## Math

This is the same equation as before just with different numbers. y=yo + (vo sin Q) t - 1/2gt^2 This time the numbers are: 0 = 1.005 + (3.021 sin 30)t - 1/2(9.8)t^2 4.9t^2 - 1.5105 - 1.005 = 0 This is the part where I am stuck. Did I do this correctly? sin

71. ## Health and Nutrition

What are some healthy nutrient sources of protein?

72. ## chem

calculate the pH of 5x10^-2 M of benzoic acid with pKa= 4.19

73. ## physics

A ladder 7.65 m long leans against the side of a building. If the ladder is inclined at an angle of 60.5° to the horizontal, what is the horizontal distance from the bottom of the ladder to the building?

74. ## orgo

What is the pH of a 5.00E-2 M solution of acetylsalicylic acid, pKa = 3.52.

75. ## physics

A high fountain of water is located at the center of a circular pool as shown in the figure below. Not wishing to get his feet wet, a student walks around the pool and measures its circumference to be 39.0 m. Next, the student stands at the edge of the

76. ## Algebra 2

a tortoise crawling at a rate of 0.1 mph, the hare wants to rest 30 more minutes before chasing the turtle at 5 mph. how many feet must the hare run to catch the turtle?

77. ## physics

An object is dropped from a height H above the ground. This free-falling object requires 0.904 s to travel the last 34 m before hitting the ground. From what height H above the ground did the object fall? The acceleration of gravity is 9.8 m/s^2. Answer in

78. ## earth

waste produced by people along the east coast of the united states has been dumped into the atlantic ocean where it is distriuted y surface ocean currents, Which coastel area is most liekly to become polluted by this waste?

79. ## math

What is 77 percent round to nearest tenth of a degcree

80. ## Math

Which is greater, the greatest whole number with 5 digits or the least whole number with 6 digits?

81. ## Linear Algebra

Solve the initial value problem: xdy/dx+4y=7x^3-10x for y(1)=4

82. ## chemistry 121

A Canadian, driving in the U.S.A., fuels their car at a cost of US$3.72 per gallon (US). The current monetary exchange rate is 0.928 US$/Can$. The density of the fuel is 0.626 g/mL. What is the mass of Can$90.00-worth of this fuel?

83. ## Math

What is 0.000698 rounded to 2 significant figures?

84. ## chemistry

"The sun emits UV radiation that can have serious health consequences. In particular, so-called UVB radiation is mostly absorbed by the ozone layer in the upper atmosphere (altitudes of 10 - 50 km), but the part that reaches the earth can cause DNA

85. ## math

Kyra drove to visit her friend. She traveled 144 miles in 2 5/8 hours. What was her average speed?

86. ## chemistry

when you burn ionic and covalent compound using Bunsen burner,what you will see?

How do you determine the ymax? I know you have to use Q which I have values that were given to me as well as vo values but I am not sure what to do with these values.

88. ## pure maths

Factorize Xsquare-6x-3

89. ## Geodetic Survey

a surveyor is trying to determine the change in hight h from the bottom to the top of a hill. If the height of instrument H is 4.5 ft the height of the object that he sights on the tower A is 6.5 ft and the zenith angle Z is 54deg 16' 25" determine the

90. ## Calculus

Check my work please? Determine if f(x)= (x^2-3x+2)/(1+x^2) has a horizontal asymptotes. If so, give the equation. So I took x^2 and divided everything by it. (x^2/x^2)-(3x/x^2)+(2/x^2) / (1/x^2)+(x^2/x^2) Cancelled out some x's and have -(3/x)+(2/x^2) /

91. ## the exceptional child

Transactional relationships exist in the families because: a.Parents tell their children how to behavior.b. children adult influence each other's behavior.c.parents cannot really learn from their children. d.teachers often make home visits. (2) special

92. ## Calculus with Analytical geometry

I'm stumped on this one. lim |x-1|sin(1/x-1) x->1

93. ## Calculus (Check)

This seems to easy. Check please. Find. Lim (x^2)-4 x->2 e I substitute in 2 (2^2)-4 e gives me 4-4 e So my answer is e^0 or 1.

94. ## math

The length of a field is three times its width. If the perimeter is 64 m, what is the width of the field?

95. ## math

Can u please help. The width of a rectangle is represented by w meters. Represent the length of the rectangle if it exceeds the width by 8 meters. Thank you

96. ## physics

a ball is thrown upward what is its maximun height? its initial vertical speed is 8.1 m/s and the acceleration of gravity is 9.8 m/s . neglet air resistance . answer in units of m

97. ## the exceptional child

Most early childhood professionals children’s agree that the terms inclusion and mainstreaming: A. Both refer to exceptional children’s participation in the general education curriculum. B. Mean the same thing. C. Are two different concepts. D. Both

98. ## Physics

Hearing damage may occur when a person is exposed to a sound intensity level of 90.0 dB (relative to the threshold of hearing) for a period of 9.0 hours. One particular eardrum has an area of 1.90 10-4 m2. How much sound energy is incident on this eardrum

99. ## physics

A subway train starting from rest leaves a station with a constant acceleration. At the end of 7.94s, it is moving at 12.3864m/s. What is the train's displacement in the first 5.57388s of motion? Answer in unites of m.

100. ## Physics

A tennis ball with a speed of 14m/s is moving perpendicular to a wall. After striking the wall, the ball rebounds in the opposite direction with a speed of 11.41m/s. If the ball is in contact with the wall for 0.0112s, what is the average acceleration of

101. ## government s1

Despite their difference , the Founding Fathers all agreed that

102. ## Geography

Is this correct? What line of longitude forms the other half of the prime meridian? When joined with the Prime Meridian the 180 degree of longitude forms a complete circle

103. ## Physics

The barrel of a rifle has a length of 0.916m. A bullet leaves the muzzle of a rifle with a speed of 621m/s. What is the acceleration of the bullet while in the barrel? A bullet in a rifle barrel does not have a constant acceleration, but constant

104. ## Physics

14. A racing car accelerates uniformly through three gears, changes with the following average speed: 20 for 2.0 s 40 for 2.0 s 60 for 6.0 s What is the overall average speed of the car?

105. ## physics

An airport has runways only 136m long. A small plane must reach a ground speed of 39m/s before it can become airborne. What average acceleration must the plane's engines provide if it is to take off safely from its airport? Answer in units of m/s^2.

106. ## Physics

Highway safety engineers build soft barriers so that cars hitting them will slow down at a soft rate. A person wearing a safety belt can withstand an acceleration of 300m/s^2. How thick should barriers be to safely stop a car that hits the barriers at

107. ## english

i need help please. What does Thomas F. Walsh, Jr's thesis propose about "Young Goodman Brown"? -because young goodman brown is a fictional short story it does not reflect any truth about life? -goodman brown enters the forest doubting the goodness of

108. ## Math

Hi I am not good with math. Please tell me how to differentiate mixed numbers, order of operation,subtraction, divide and multiplication etc. Thanks!

109. ## math

choose a natural between 1 and 20 inclusive. what is the probability that the number is a mutiple of 3

110. ## Physics

If a satellite is orbitting the earth 710km above the earths surface, and it's velocity is 7,406.8 meters/sec, what is it's cetripedal acceleration??

111. ## physics

Light-rail passenger trains that provide transportation within and between cities are capable of modest accelerations. The magnitude of the maximum acceleration is typically 1.3 {\rm m}/{\rm s}^{2}, but the driver will usually maintain a constant

121. ## Economics

The demand for cosmetic surgery is more elastic than the demand for Botox treatments, would this be true or false? My thoughts are true.

122. ## chemistry

if an iceberg has a volume of 8660 cubic feet, what is the mass in kg of the iceberg?

123. ## Algebra..

Help? If f = (1, 2), (2, 3), (3, 4), (4, 5), g = (1, -2), (3, -3), (5, -5), and h = (1, 0), (2, 1), (3, 2), 1. f+g 2. f-g 3. f*g

124. ## Algebra..

How to Solve This? f(x)=|x-5| g(x)=(1)/(x) 1. h(x)=|(1)/(x) -5|

125. ## calculus

To find the equation of a line, we need the slope of the line and a point on the line. Since we are requested to find the equation of the tangent line at the point (64, 8), we know that (64, 8) is a point on the line. So we just need to find its slope. The

126. ## Algebra..

Find the slope of the straight line that passes through the given points or state that the slope is undefined. Then indicate if the line through the points rises (left to right), falls (left to right), is horizontal, or is vertical. 1. (7, 4) and (1, 1) 2.

127. ## Algebra..

HELP. Problems 4 - 7: Write an equation for the line in point/slope form and slope/intercept form that has the given condition. 4. Slope = 3/2 and passes through the origin. 5. x-intercept = 4 and y-intercept = -3

128. ## world history

The popularity of an individual Hindu deity was largely a reflection of a) its ranking by the Hundred Schools of Thought. b) the approval it received from Siddhartha Gautama. c) its pre-Aryan origin. d) the size of its pyramids. I think it's A but I'm not

129. ## Algebra..

help? Give the slope and y-intercept of the given line and then graph it. 8. 2x-3y=6 9. y=-2x 10. y=3 11. x+2=0

130. ## Algebra..

Help ? Find the slope of the line that is a) parallel and b) perpendicular to the given line. 1. x=-8 2. y=10

131. ## physics

A 316-kg boat is sailing 12.0° north of east at a speed of 1.60 m/s. 39.0 s later, it is sailing 36.0° north of east at a speed of 4.00 m/s. During this time, three forces act on the boat: a 31.4-N force directed 12.0° north of east (due to an auxiliary

132. ## Integrated Marketing Communications

Research any firm local or foreign and present a report and critique of their marketing communications

133. ## physics

A wire tooth brace used by orthodontists. The top-most tooth is protruding slightly, and the tension in the wire exerts two forces at 16 º angle on this tooth in order to bring it back into alignment. If the forces have the same magnitude of 19.5 N, what

134. ## hp

each case of almond bars contains 9 smaller boxes. each smaller box contains 24 almond bars. how many almond bars are in each box

135. ## Integrated Marketing Communications

develop an IMC plan for a business.

What is base measurement? thanks

X+12=2x+6

138. ## economics

the currency in Great Britain is pound and the price of a particular British car is 12,000. suppose the exchange rate is 0.67 per dollar. what iis the price of the British car in United States dollars?

139. ## math

"If the tire is 48 inches around what is its radius?

140. ## English

In the Tale of Two Cities question. Besides the foreshadowing of the blood bath to come, what does the people's response to the spilled wine show us?

141. ## Economics

The country of New Zealand decides to take 50% of its nation’s lottery money and use it to buy 1,000 acres of common grazing land in every county upon which any New Zealand shepherd may graze their sheepfor free, no strings attached. Based upon what you

142. ## PHYSICS help!!!!!!

A commuter train travels between two downtown stations. Because the stations are only 1.36 km apart, the train never reaches its maximum possible cruising speed. During rush hour the engineer minimizes the travel time t between the two stations by

143. ## science

A 49 kg person drinks 270. g of milk, which has a "caloric" value of approximately 3.0 kJ/g. If only 16% of the energy in milk is converted to mechanical work, how high (in meters) can the person climb based on this energy intake? [Hint: The work done in

144. ## Antarctica

In 1973, Congress enacted the Endangered Species Act (ESA) to protect plants and animals from extinction. Many methods are used for protection. Residential or commercial development may be banned in an area that is set aside to protect animal or plant

145. ## Math

2. Find the product of 2 1/2 and 2/5. a. 2 2/10 b. 2 3/7 c. 2 4/9 d. 2 9/10 3. Which of the following makes the statement true? 1/5^0 = ? a. 1 b. -1 c. -5 d. 0 4. The area of a certian state is 840,000 square miles. What is this area in scientific

146. ## Algebra 2 (Math)

If A=(0,-17), B=(4,-5), and C=(12, -1), what is the length of the altitude from C to AB

Can someone give me an example or template how to write a practicum proposal for mediation.

148. ## math

a piece of wire 3.5m long was cut into lengths each measuring 0.05m long.Calculate the number of pieces obtained.

149. ## physics

A roller coaster travels 101 ft at an angle of 56.8 above the horizontal. How far does it move horizontally?

150. ## chemistry

Find the potential energy, V(r), and the magnitude of the force, | F |, associated with: (a) the interaction between a proton and an electron separated by a distance of 0.529 Å (b) the interaction between the nucleus of Neon (Ne) and an electron separated

151. ## social studies

what are the 4 maps. phyical, population , polical waht is the last one please

152. ## Math

How do i round off the decimal 0.9683 to the nearest tenth, hundredth, and thousandth

153. ## Math

Which is the greatest number and why: .004 or .04

154. ## calculus

Calculate the following integral: ∫ dx / x(1 - √x)^2

155. ## social studies

what are the 4 maps. phyical, population , polical waht is the last one please

156. ## Math

You decide to build a pyramid out of wooden blocks. Each block must rest on the corners off 4 other blocks. If there is one block on top and 36 on the bottom, what is the total number of blocks you will need to complete the pyramid?

157. ## Calc 3

Find the limit, if it exists. (If an answer does not exist, enter DNE.) lim (x, y)→(0, 0) of (x^2 + y^2)/[((x^2 + y^2 +64)^.5)-8]

158. ## Chemistry

what is 39.5 grams of HCl in moles?

159. ## chemistry

the vapour pressure of water at 20 degree celcius is 18 mm hg .if the relative humidity is 35 % the weight per litre of air at 20 degree celcius is ?

Given a homogenous liquid mixture of sodium chloride (salt) and water, what would be the best method to separate these substances? What is the process. Please explain.

161. ## Math

Jim has a total of 77 red and blue marbles. The number of blue marbles is 5 more than twice the number of red marbles. How many red marbles are there?

162. ## Chemistry

Calculate the number of grams necessary of C6H12O6 to make 1.00 ml of 0.025 M glucose.

163. ## Physics

7. A cat pushes a ball from a 7.00 m high window, giving it a horizontal velocity of 0.20 m/s. How far from the base of the building does the ball land? (Assume no air resistance and that ay= g = 9.81 m/s2.)

164. ## Physics

A diver running 1.1 m/s dives out horizontally from the edge of a vertical cliff and 3.3 s later reaches the water below. How high was the cliff? How far from its base did the diver hit the water?

165. ## Biology

If you added .1 M NaOH to 1 M HCO2H a few millimeters at a time what would happen?

9 + x = 17 I know that x=8 but how did you get it Thanks

167. ## math 12

A)a shed, in the shape of a square based prism, is to have volume 800meters cubed. determin the dimentions of the shed, with the minimum surface area. B)how would the answer change if the minimum surface area did not include the bottem of the shed?

168. ## science

the ph of a 0.280m solution of a weak base. B has been measured ph --8.69. using this information. calculate the base ionisationconstant kbof b

169. ## Chemistry

How many watts are in a kWh? Or how do you convert 30 kWh into joules/sec?

170. ## geometry

express 0.000 000 291 in scientific notation

171. ## economics

In what areas of the economy are jobs growing most rapidly? Is this due to a lack of technological innovation in these areas?

9 + x = 17 I know that x=8 but I don't know how you figure it out

173. ## Math

If you had a new business and you had 30 customers the first week and 55 customers the second week and 80 customers the third week, what would you project for week 4? Explain how you arrived at your answer.

174. ## CSU Fresno

Give an example of languages L1 and L2 that satisfy the conditions (a) L1L2=L2L1, (b) L2 is a proper nonempty subset of L1, and (c) L2≠{ε}.

175. ## math

Steven collected data from 20 college students on their emotional responses to classical music. Students listened to two 30-second segments from “The Collection from the Best of Classical Music.” After listening to a segment, the students rated it on a

176. ## math

Billie wishes to test the hypothesis that overweight individuals tend to eat faster than normal-weight individuals. To test this hypothesis, she has two assistants sit in a McDonald’s restaurant and identify individuals who order the Big Mac special for