I don’t understand how I would work this out

Describe in detail how you would construct a 95% confidence interval for a set of 30 data points whose mean is 20 and population standard deviation is 3. be sure to show that you know the formula and how to plug into it. also, clearly state the margin of error.

Given the equation f(x)=a(b)x where the initial value is 40 and the growth rate is 20% what is f(4)

What is the length and width of a 84.5 square foot rug? will mark