An arch in the firm of a semicircle was over a 40 inch wide doorway. Find the length of the arch.

This is so harddd! solve. 1 + 1 = solve 4 + 4 = solve 3 x 3

Assume that the weights of quarters are normally distributed with a mean of 5.67 g and a standard deviation 0.070 g. a vending machine will only accept coins weighing between 5.48 g and 5.82 g. what percentage of legal quarters will be rejected? round your answer to two decimal places.

What are the solutions of the system? solve by graphing. y = -x^2 - 3x + 2 y = -2x + 2