a. Having obtained a random sample from a population, you wish to use a chi-squared test...

a. Having obtained a random sample from a population, you wish to use a chi-squared test to decide whether the population distribution is standard normal. If you base the test on six class intervals having equal probability under H₀, what should be the class intervals?

b. If you wish to use a chi-squared test to test H0: the population distribution is normal with μ = .5, σ = .002 and the test is to be based on six equiprobable (under H₀) class intervals, what should be these intervals?

c. Use the chi-squared test with the intervals of part (b) to decide, based on the following 45 bolt diameters, whether bolt diameter is a normally distributed variable with μ = .5, in., σ = .002 in.