What is a proof of the volume of a pyramid

Find the x coordinate of the point.

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.

Which point lies on a circle with a radius of 5 units and center at p(6, 1)?