Need help l don’t understand new topic

Sandy works at a clothing store. she makes $7 per hour plus earns 15% commission on her sales. she worked 75 hours over the last two weeks and had a total of $2,566 in sales before taxes. which of the following is closest to how much she will earn in hourly wages and commission for those two weeks?

Rewrite the following without an exponent. (5/8)-1

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.