Can y’all help me I need help for this test i know y’all smart can y’all please help y’all boy out

Let the mean of the population be 38 instances of from 6" - 9" hatchings per nest, and let the standard deviation of the mean be 3. what sample mean would have a confidence level of 95% or a 2.5% margin of error?

Which represents the solution set of the inequality 5x-9 < 21? a. x < 12/5 b. x > 12/5 c. x > 6 d. x < 6

Anyone? 15m is what percent of 60m; 3m; 30m; 1.5 km?