Petra invested $6,000 at 6.5% simple interest for 3 years. Martin invested $6,000 at 5% for 42 months. Who had more money at the end of their investments and by how much?

Afactory makes propeller drive shafts for ships. a quality assurance engineer at the factory needs to estimate the true mean length of the shafts. she randomly selects four drive shafts made at the factory, measures their lengths, and finds their sample mean to be 1000 mm. the lengths are known to follow a normal distribution whose standard deviation is 2 mm. calculate a 95% confidence interval for the true mean length of the shafts. input your answers for the margin of error, lower bound, and upper bound.

How to simply and write the answer n a whole number

Change negative exponents to positive, then solve