I need help! Step by step, please!

Fish story: According to a report by the U.S. Fish and Wildlife Service, the mean length of six-year-old rainbow trout in the Arolik River in Alaska is 477 millimeters with a standard deviation of 39 millimeters. Assume these lengths are normally distributed. (a) Find the 41" percentile of the lengths. (b) Find the 75 percentile of the lengths. (c) Find the first quartile of the lengths. (d) A size limit is to be put on trout that are caught. What should the size limit be so that 15% of six-year-old trout have lengths shorter than the limit? Part 1 of 4 The 41 percentile of the lengths is Part 2 of 4 The 75 percentile of the lengths is Part 3 of 4 The first quartile of the lengths is Part 4 of 4 The size limit should be millimeters