5.4 x 10 to the 3rd power to standard form

Keith runs 5 miles in 38 minutes. at the same rate, how many miles would he run in 57 minutes

The interior angles formed by the sides of a hexagon have measures that sum to 720°. what is the measure of angle a? enter your answer in the box. m∠a= °

Rena used the steps below to evaluate the expression , when . step 1: substitute into the expression. step 2: simplify the parentheses. step 3: evaluate the power to a power. step 4: use reciprocals and find the value. in which step did rena make the first error?