Concerns about climate change and CO₂reduction have initiated the commercial production of blends of biodiesel (e.g., from renewable sources) and petrodiesel (from fossil fuel). Random samples of 33 blended fuels are tested in a lab to ascertain the bio/total carbon ratio.

(a)If the true mean is .9560 with a standard deviation of 0.0020, within what interval will 99 percent of the sample means fall?(Round your answers to 4 decimal places.)

The interval is from _____ to _____

(a)Find the standard error of the mean for each sampling situation (assuming a normal population).(Round your answers to 2 decimal places.)

Standard Error

a. = 16, n = 16

b. = 16, n = 64

c. = 16, n = 256

(b)What happens to the standard error each time you quadruple the sample size?

The standard error is _______ by half.