Carbon monoxide? (CO) emissions for a certain kind of car vary with mean 3.977 ?g/mi and standard deviation 0.7 ?g/mi. A company has 60 of these cars in its fleet. Let y overbar represent the mean CO level for the? company's fleet. ?

a) What's the approximate model for the distribution of y overbar?? Explain.

?b) Estimate the probability that y overbar is between 4.1 and 4.3 ?g/mi. ?

c) There is only a 10?% chance that the? fleet's mean CO level is greater than what? value?

Suppose an object that has a mass of 8.8 kg and slides on ice at a speed of 13 m/s. It runs into another object, which is initially at rest and has a mass of 11.10 kg. They naturally stick together (in a perfectly elastic colision). What is their final velocity in (m/s)?

A 160 kg merry-go-round has a radius of 2.5 m and it is rotating with an angular velocity of 0.7 rev/s. What is its angular velocity after an at rest 86-kg person gets onto it by grabbing its outer edge?

Two identical concave mirrors are set facing each other 2.8 mapart. A small lightbulb is placed halfway between the mirrors. A small piece of paper placed just to the left of the bulb prevents light from the bulb from directly shining on the left mirror, but light reflected from the right mirror still reaches the left mirror. A good image of the bulb appears on the left side of the piece of paper.

what is the focal length of each mirror?

previous answers were both = 1.4 and both = 0.7 and these are not correct.

3. A random sample of 64 lighting flashes in a certain region resulted in a sample average radar echo duration of 0.7 sec and a sample standard deviation of 0.32 sec.

• (a) Construct a 89% confidence interval for the true mean radar echo duration.

• (b) Explain the meaning of your interval in such a way that someone who had not ever studied statistics would understand.

• (c) At a 0.11 level of significance, can you conclude that the true radar echo duration differs from 0.78 sec? Explain why

A farmer wants to determine if the average growth of sunflowers is 4.5 ft per year or not. A sample of 41 sunflowers had a mean of 4.25 ft per year and a standard deviation of 0.7 ft per year.

a) This is a two-sided test;state the hypotheses.

b) State the rejection region for α=0.05

c)Will you reject or retain the null hypothesis? Show all work to support your answer.

d) Find the 95% confidence interval for average growth of sunflowers.Is the value of µ₀ inside the 95% confidence interval?

Colt Manufacturing has two? divisions: 1)? pistols; and? 2) rifles. Betas for the two divisions have been determined to be beta (pistol)= 0.7 and beta ?(rifle)=1.3 The current? risk-free rate of return is 4?%, and the expected market rate of return is 10% The? after-tax cost of debt for Colt is 3.5%. The pistol? division's financial proportions are 37.5% debt and 62.5% ?equity, and the rifle? division's are 47.5% debt and 52.5% equity.

a. What is the pistol? division's WACC?

b.??What is the rifle? division's WACC?

A neutron star and a white dwarf have been found orbiting each other with a period of 26 minutes. If their masses are typical, what is their average separation? Compare the separation with the radius of the sun, 7 ✕ 10⁵ km. (Hints: Use the version of Kepler's third law for binary stars,

M_A + M_B =

;

make sure you express quantities in units of AU, solar masses, and years. Assume the mass of the neutron star is 2.0 solar masses and the mass of the white dwarf is 0.7 solar masses.)

Ans:
______________ solar radius

Considering the transition matrix below, what is the probability that a bond initially rated B will be in default (rating D) at the end of two years? Show how you derived your answer.                     

1. A study was carried out to determine the putting accuracy of golf players on uphill and downhill putts from five feet. In a sample of 100 uphill putts, 90 putts were successful. In a sample of 80 downhill putts, the number of successful putts was 60. Assume α=.05

1. Is there evidence that the proportion of uphill putts successfully made is larger than downhill putts?
2. Suppose p1=0.95 and p2=0.7. What is the sample size required to have a power of test =0.95?
3. Construct the appropriate 95% CI and interpret this interval