Joan invests $800 at 12 1/2% per annum compound interest monthly. What is the amount of interest at the end of the first year? plz help me do this question?

The lengths of nails produced in a factory are normally distributed with a mean of 4.91 centimeters and a standard deviation of 0.05 centimeters. find the two lengths that separate the top 4% and the bottom 4%. these lengths could serve as limits used to identify which nails should be rejected. round your answer to the nearest hundredth, if necessary.

Elizabeth claims that the fourth root of 2 can be expressed as 2^m since (2^m)^n = 2. find the values of m and n for the case where elizabeth's claim is true.

Amachine part consists of a half sphere and a cylinder, as shown in the figure. the total volume of the part is π cubic inches.