PLS HELP!! Solve for an angle in right triangles

BC = ???

round your answer to the nearest hundredth

School has 204 sixth grade students. if the sixth grade is 30% of the total school, how many students are in the middle school?

Complex numbers multiply √-4 * √-25 and show all intermediate steps. alternative notation is sqrt(-4) * sqrt(-25).

Write an algebraic expression to match each statement a. four less than 8 times a number b. twice the difference of a number and six c. nine from a number squared