Given x=7 y=3 and z=10, calculate the value of:
5x =

A. 127 cm^2 b. 144.5 cm^2 c. 172 cm^2 d. 50 cm^2

Koji is installing a rectangular window in an office building. the window is 823 feet wide and 534 feet high. the formula for the area of a rectangle is a=bh. what is the area of the window? enter your answer as a mixed number in simplest form in the box. $$ ft2

Is the power produced directly proportional to the wind speed, give reasons for your answer?