Um can someone basically explain the steps to finding this thank you !

Which best explains why this triangle is or is not a right triangle?

Four congruent circular holes with a diameter of 2 in. were punches out of a piece of paper. what is the area of the paper that is left ? use 3.14 for pi

The annual snowfall in a town has a mean of 38 inches and a standard deviation of 10 inches. last year there were 63 inches of snow. find the number of standard deviations from the mean that is, rounded to two decimal places. 0.44 standard deviations below the mean 2.50 standard deviations below the mean 0.44 standard deviations above the mean 2.50 standard deviations above the mean