Can anyone help with this question?

Show your workcan a right triangle have this sides? *how to prove it without using the pythagorean theorema*

Select the margin of error that corresponds to the sample mean that corresponds to each population: a population mean of 25, a standard deviation of 2.5, and margin of error of 5%

If you are dealt 4 cards from a shuffled deck of 52? cards, find the probability that all 4 cards are diamondsdiamonds.