# Questions Asked onMarch 25, 2012

1. ## Math-

A ball is thrown vertically upward with an initial velocity of 96 feet per second. The distance s (in feet) of the ball from the ground after t seconds is s(t)=96t-16t^2 a.) at what time will the ball strike the ground b.) for what time t is the ball more

secx/secx-tanx=sec^2x+ secx+tanx

3. ## Chemistry

Write the acid-dissociation reaction of nitrous acid (HNO2) and its acidity constant expression.

4. ## chemistry- electrochemical cell

What makes this an oxidation-reaction? 3Ag2S+2Al(s) -> Al2S3+6 Ag(s)? Write the half-reactions showing the oxidation and reduction reactions. Identify which is the oxidation reaction and which is the reduction reason. What is oxidized in the reaction? What

5. ## Chemistry

The reaction: H2PO4- + HAsO42 ---> HPO4- + H2AsO4- Which one of the sets above lists both of the base species involved in the equilibrium? I'm confused and couldn't identify the conjugate acids and bases properly. Could Dr.Bob explain abt this problem ?

6. ## statistics

The number of pizzas consumed per month by university students is normally distributed with a mean of 9 and a standard deviation of 5. What is the probability that in a random sample of size 10, a total of more than 80 pizzas are consumed? (Hint: What is

7. ## Physics

A 60kg front seat passenger in a car moving initially with a speed of 18m/s (40 MPH) is brought to rest by an air bag in a time of 0.4s a. What is the impulse acting on the passenger? b.What is the average force acting on the passenger in this process?

8. ## personal finance

Alison's car is valued at $14,000, and she owes$12,000 on it. What is her current equity?

9. ## chemistry

If all the energy obtained from burning 1.23 pounds of propane (fuel value is 11.09 kcal/g) is used to heat 125.0 kg of water at an initial temperature of 21.8 °C, what is the final temperature? Hint: The heat, q, released by burning propane is absorbed

10. ## chemistry

Suppose that you place exactly 100 bacteria into a flask containing nutrients for the bacteria and that you find the following data at 37 °C: TIme (s) number of bacteria 0 100 19 200 38 400 57 800 76 1600 what is the rate order? What is rate constant? how

11. ## Calculus

A function f is defined on the interval [0,4], and its derivative is e^sinx-2cos3x a. on what interval is f increasing? b. at what value(s) of x does f have a local maxima? c. how many points of inflection does f have? *calculator is allowed for this

12. ## physics

A 4.5 cm tall object is placed 20 cm in front of a spherical mirror. It is desired to produce a virtual image that is upright and 3.5 cm tall. (a) What type of mirror should be used? concave mirror convex mirror (b) Where is the image located? (Your answer

13. ## spanish

Yo ______ lavo ______ manos y ______ cara. ______ cepillo ______ dientes y ______ cepillo ______ pelo. Yo ______ pongo ______ ropa.

14. ## calculus

A searchlight rotates at a rate of 4 revolutions per minute. The beam hits a wall located 9 miles away and produces a dot of light that moves horizontally along the wall. How fast (in miles per hour) is this dot moving when the angle between the beam and

15. ## chemistry

The solubility products of AgBr and Ag3PO4 are 5.0 10-13 and 1.8 10-18, respectively. If Ag+ is added (without changing the volume) to 1.00 L of a solution containing 0.31 mol Br ‾ and 0.31 mol PO43-, calculate the molarity of Ag+ ions required to

16. ## Chemistry

How do you prepare a 0.4 M soultion of copper sulfate in water starting with solid copper sulfate and water?

17. ## college physics

A 0.50-kg block slides along a small track with elevated ends and a flat central part. The flat part has a length L = 1.85 m. The curved portions of the track are frictionless, but for the flat part the coefficient of kinetic friction is 0.103. The block

18. ## Physics

A rifle with a mass of 1.2 kg fires a bullet with a mass of 6.0 (0.006kg). The bullet moves with a muzzle velocity of 600 m/s after the rifle is fired. a. What is the momentum of the bullet after the rifle is fired? b. If external forces acting on the

19. ## Math

A function f is defined on the interval [0,4], and its derivative is e^sinx-2cos3x a. on what interval is f increasing? b. at what value(s) of x does f have a local maxima? c. how many points of inflection does f have? *calculator is allowed for this

20. ## physics

A 3.00x10^-3 kg lead bullet enters a target with a speed of 2.00x10^2 m/s and comes to rest within the target. Calculate the rise in temperature of the bullet assuming that 80.0% of the heat produced is absorbed by the bullet. The Specific heat of lead is

21. ## physics

A 1.75-kg wooden block rests on a table over a large hole as in the figure below. A 4.60-g bullet with an initial velocity vi is fired upward into the bottom of the block and remains in the block after the collision. The block and bullet rise to a maximum

22. ## Biology

When you measure your heart rate for less than 20 seconds , why is it less possible for the results to be reliable? When you measure your heart rate for more than 20 seconds, why is it still less possible for the results to be reliable?

23. ## Physics

Tom the train and Dan are involved in an elastic collision. A 2.5 kg Tom is, at rest but is approached head-on by a 5.0 kg Dan moving at 0.60 m/s. The force-separation graph for the ensuing collision is given: the picture of the graph is found here:

24. ## Statistics

Computer Depot is a large store that sells and repairs computers. A random sample of 110 computer repair jobs took technicians an average of 93.2 minutes per computer. Assume that o is known to be 16.9 minutes. Find a 99% confidence interval for the

25. ## Chemistry

use the Ksp of SnS2= 1.0X10^-70 and calculate the pH of a hydrogen sulfide solution needed to precipitate 99.99% of the tin(IV) ion assuming [Sn^4+]=0.05M and that [H2S]=0.10M.

62. ## Physics

A 15 kg child stands on the edge of a small merry-go-round of radius 2.0 m. If the merry-go- round turns at a steady rate of 11 rpm, calculate the magnitude and direction of the net force on the child.

63. ## algebra

you can paint a room in 8 hours. your friend and you can paint a room in 5 hours together. how long does it take your friend alone?

64. ## physics

A jet plane is traveling at a constant speed in a straight line in level speed. What does this tell you about the forces acting on it, what forces are acting on it .

65. ## physics

A 1200 kg boat accelerates steadily at 0.05 m/s^2 in a straight line . Are the forces on this boat balanced or unbalanced?

66. ## Chemistry

I don't get this at all. A beaker with 105mL of an acetic acid buffer with a pH of 5.00 is sitting on a bench top. The total molarity of acid and conjugate base in this buffer is 0.100 M. A student adds 8.40 mL of a 0.470 M HCl solution to the beaker. How

67. ## Chemistry

how do I find the pH of a buffer solution given that 0.010M NH3 mixed with 0.0030M NH4Cl. Also... a 0.010M HF solution is mixed with 0.030M KF. FIND THE pH of this mixed solution.

68. ## Chemistry

help...If exactly 5.0 mL of HNO3 will neutralize 15 mL of 2.0 M NaOH, what is the molarity of the HNO3 solution? Have no idea what to do. thank you.

69. ## Finance

A 20-year, $1,000 par value bond has a 9% annual coupon. The bond currently sells for$925. If the yield to maturity remains at its current rate, what will the price be 5 years from now

70. ## Statistics

A random sample of 14 evenings at the O'Sullivan house hold showed that the family received an average of 2.4 solicitation calls each evening. The sample standard deviation was s= 0.9. Find a 99% confidence interval for the population mean number of

71. ## Statistics

Long term experience showed that after a type of eye surgery, recovery time has a mean of u = 5.3 days in a hospital. A random sample of 40 patients, with this type of eye surgery, were treated as outpatients during recovery and the sample mean recovery

72. ## chemistry

Calculate the pH range required to separate 99.99% of Cr3+ from Zn2+ by precipitation of Cr(OH)3(s) in a solution that is initially 0.034 M in both Cr3+ and Zn2+. Use the Ksp values from Table 16.2 of Chang and calculate the pH to the nearest 0.01 pH unit.

73. ## Physics

trap door of length and width 1.65 m is held open at an angle of 65.0 degree with respect to the floor. A rope is attached to the raised edge of the door and fastened to the wall behind the door in such a position that the rope pulls perpendicularly to the

74. ## precal

1/tanx-secx+ 1/tanx+secx=-2tanx so this is what I did: =tanx+secx+tanx-secx =(sinx/cosx)+ (1/cosx)+(sinx/cosx)-(1/cosx) =sinx/cosx+ sinx /cosx= -2tanxI but I know this can't be correct because what I did doesn't end as a negatvie:( please help

75. ## Math

What positive value of b makes 9^2-bx+4 a perfect square trinomial? How would you solve this problem? Thanks

76. ## chemistry

A 600ml sample of a saturated solution of MgCO3 is reduced to 125 ml by evaporation. What mass of MgCo3 is formed? Ksp=4*10^-5

77. ## statistics

A person can order a new car with a choice of 9 possible colors, with or without ac, with or without heated seats, with it without anti lock breaks, with or without power windows and with or without a CD player. How many different ways can a new car be

78. ## Physics

A wheel's uniform angular acceleration is constant. Initially its angular velocity is zero. During the first 1.0 s time interval, it rotates through an angle of 90.0°. (a) Through what angle does it rotate during the next 1.0 s time interval? (b) Through

79. ## Spanish

Fill in the blank. 1. Los amigos están viajando por un país europeo. Los amigos están viajando por _____________________. 2. Están haciendo un viaje que no cuesta mucho. Están haciendo un viaje _______________. 3. Lo están pasando muy bien. Se

80. ## chemistry-balanced redox equations

Use the following steps to balance the redox reaction below: Mg + Au+ Mg2+ + Au a. Write the oxidation and reduction half-reactions. Make sure each half-reaction is balanced for number of atoms and charge b. Multiply each half-reaction by the correct

81. ## physics

Find the mass in grams of a carbon dioxide molecule.

82. ## physics

A 1-kg mass (the blue mass) is connected to a 8-kg mass (the green mass) by a massless rod 67 cm long, as shown in the figure. A hole is then drilled in the rod 40.2 cm away from the 1-kg mass, and the rod and masses are free to rotate about this pivot

137. ## calculus

1. Consider the function f(x) = X^(4/3) +4x^(1/3) on the interval -8 ≤ x ≤ 8. a. Find the coordinate of all points at which the tangent to the curve is a horizontal line. b. Find the coordinate s of all points at which the tangent to the curve is a

138. ## science fair

in my science fair report school layout they want us to write a paragraph on testing my hypothesis and before that they asked us to write the procedure. i wrote the procedure now do i rewrite it for testing my hypothesis? or do i write something else

139. ## English

Could you please check my sentences, please? Thank you, Writeacher. 1) You can't get out of it: you must confess that you have broken the vase. We were having dinner when the lights went out. 2) The teacher invited me to look up the unknown words in the

140. ## Algebra

A ball is thrown up with an initial velocity of 32 feet per second. How many seconds will it take for the ball to return to the ground using the formula h=vt-16t^2?

141. ## Religion

What is a good way to define a totem pole?

A farmer wants to fence in 60 000m^2 of land in a rectangular field along a straight road. The fencing that he plans to use along the road is $10 per meter and the fencing that he plans to use for the other three sides costs$5 per meter. a) How much of

143. ## physics

A bug that has a mass mb = 1 g walks from the center to the edge of a disk that is freely turning at 38 rpm. The disk has a mass of md = 11 g. If the radius of the disk is R = 30 cm, what is the new rate of spinning in rpm?

144. ## physics

A cylinder of mass M=58 kg, radius R=1.3 m and moment of inertia I=(1/2)MR2 is initially rotating around its central axis with an angular velocity ωi= 1.8 rad/s. A tangential force F of constant magnitude applied to the edge of the cylinder during 5.9 s

145. ## physics

A spool of thin wire pivots on a shaft with friction. The wire is pulled by a hanging mass M=1.50 kg. Upon starting from rest and falling a distance D=1.65 m, the mass has a speed V=2.00 m/s. Calculate the energy lost to friction during that time. Inner

146. ## Statistics

How long does it take to have food delivered? A Chinese restaurant advertises that the mean delivery will be no more than 30` minutes. A random sample of delivery times is shown below. Based on this sample data, is the mean delivery time different than 30

147. ## physics

When the crampton coal-fired train engine was built in 1852 , its mass was 48.3t ( 1.0 t= 1.0*10^3) and its force capability was rated at 22.4 kN. Assuming it was pulling train cars whose total mass doubled its own was and the total friction on the engine

149. ## Math

(4.44e-2 - x) (8.06e-2 - x) / (0.331 + 2x)^2 = 1.80e-2 I need to rearrange this equation so that I can get a,b, and c, for the quadratic equation but I am not sure how to do this. Thank you for the help. Math(Please answer, thank you) - bobpursley, Sunday,

150. ## Chemistry

I have 2 questions on columns used in the Gas Chromatography-Flame Ionisation Detector (GC-FID) instrument: - 1) If a capillary column is left in the GC-FID instrument for 2 months with the instrument switched off (i.e. instrument is not in use),will this

151. ## AIU

You are the lead human–computer interaction (HCI) engineer on a major defense project supporting the government and its integration of a new system and application design for use by federal investigators. Part of your job is to elicit and define the user

152. ## calculus

1. Consider the function f(x) = X^(4/3) +4x^(1/3) on the interval -8 ≤ x ≤ 8. a. Find the coordinate of all points at which the tangent to the curve is a horizontal line. b. Find the coordinate s of all points at which the tangent to the curve is a

153. ## Criminal Justice

If judicial review were eliminated, what alternative means could be used to interpret the meaning of the Constitution?

154. ## Physics

A helicopter winches up an injured person from a boat. The person plus equipment has a mass of 104 kg. If the height of the lift is 84 m and it is carried out at a uniform rate over 70 s, what is the power expended by the helicopter's winch motor? Assume

155. ## physics

The force on a wire is a maximum of 6.00\times 10^{ - 2} {\rm{N}} when placed between the pole faces of a magnet. The current flows horizontally to the right and the magnetic field is vertical. The wire is observed to "jump" toward the observer when the

156. ## Religon

Unscrable mastcrane

157. ## physics

If we were to find advanced life on a planet which orbited reasonably near to a star of temperature 30000 Kelvin, to what wavelength of radiation (measured in nanometers, nm) might we reasonably predict their eyes would be most sensitive?

158. ## Physics

What is the total power, or radiant flux, (in megawatts) of a spherical object of temperature 873 K and radius 7 meters, if we assume that it radiates like a perfect blackbody? (To get an answer in megawatts, take your answer in watts and divide by a

159. ## physics

If a more complicated atom has two energy levels for its electrons at (-15) eV and (-30.1) eV, what is the wavelength of the photon (in nm) that is emitted when an electron transitions between these two levels?

160. ## TEC/401

HOW the internet policies of some countries may effect a company's ability to expand globally? Current and potential uses of technology for the global success of business objectives?

161. ## physics

Is their anyone that goes to CA homeschooling that can help with roller coaster portfolio?

162. ## Guest

they'll tell you they love you and THAN/THEN just leave you.

163. ## ENG227

Part One: Analytical Report on a Targeted Sales Letter Your supervisor has asked that you file a brief informal report (approx. 2 single-spaced pages, 500-750 words, plus references) on the background of the company you have chosen to solicit with your

164. ## Math

I'm stuck on my homework, and my parents don't know how to do expanded algorithm

165. ## LIFE ORIENTATION

IN 10-15 LINES CRITICALLY DISCUSS 5 WAYS IN WHICH THE HUMAN OR ENVIRONMENTAL PROBLEM IMPACTS ON THE COMMUNITY.PROVIDE RELEVENT SOURCES TO SUPPORT YOUR CLAIMS.

166. ## physics

What is evaporation,boiling,cryometer

167. ## Living Environment

Tell whether each of the following substances that is filtered from the blood in the glomerulus is absorbed, excreted as part of the urine, or both Water________________________________ amino acids_________________________ glucose____________________

168. ## physics

Show your work for how the formula was used to calculate a final answer! GPE for second hill: ___ _________________++ Describe how conservation of energy applies to a roller coaster ride from start to finish. This is the last part of roller coaster I'd

169. ## MS. SUE OR ANYONE PLS. HELP ME..technical writing

please help me if this is correct i have made for my homework. instruction is below: As a customer service manager for a local software development company, you want to create a user manual for one of the software applications your company develops. The

170. ## Geometry

Which of the following can be used to describe the triangle with the vertices listed below? F(-1, 1), G(-8, 1), H(-9, -10) I. acute II. obtuse III. right IV. scalene V. isosceles VI. equilateral -----Please show me how you got the answer

171. ## Philosophy

Why did Hobbes name his text Leviathan?

172. ## Physics

Find the velocity of microwaves having wavelength of 0.75m and frequency 2.75X10^10hz

173. ## Algebra

Two perpendicular lines with the equations y=1/3x+9 and y=mx-3 contain consecutive sides of a rectangle. What is the value of m in the second equation?

174. ## English

In the book "Here lies Arthur", what does the lady of the lake give to Peredeur?

224. ## Derivatives

differentiate and simplify y= (e^x - 1) / x^2

225. ## child psychology

I still need help with this question Which young adult is at risk of long term identity foreclosure or diffusion? A. A college graduate who switces majors B. An aspiring chef who has no opportunity for culinary training. C.A young woman with several

226. ## ps 189

if a aluminum can has a radius of 10cm and a height of 20 cm. how many square cm of aluminum does it take to make such a can.

227. ## healthcare

What information should you share with others at workplace that promotes to aged care

228. ## science

2 mole jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj

229. ## healthcare

how can you review and develop your work performance at aged care

230. ## Science

What does a thermohygrometer do?

231. ## Math

How do you do \$1.00 for 6 lemons ?

232. ## precal

(1/tanx-secx))+(1/(tanx+secx))=-2tanx

233. ## social studies

How were religion and the Roman government related?

234. ## English

Writeacher, I'm still working on my paragraph on the presentation of the Irish school. I really hope you'll be there in three hours' time to check if everything is OK. By the way, can you suggest a website, on which (?) phrasal verbs are grouped according

235. ## Operations Management

Explain the key interactions among marketing, design, manufacturing, and finance in product development?

236. ## Criminal Justice

Should judicial review be eliminated? Provide a detailed explanation for your answer.

237. ## Physics

A helicopter winches up an injured person from a boat. The person plus equipment has a mass of 104 kg. If the height of the lift is 84 m and it is carried out at a uniform rate over 70 s, what is the power expended by the helicopter's winch motor? Assume

238. ## chemistry

Methanol WHat is the chemical formula? What is the molecular formula?

239. ## network topology

what type of home network topology do you utilize? does the physical topology differ from its logical topology? if you do not have a homework, research a friends network and use that data in your response.