Select the correct answer.
A washing machine uses 1.8 5 10 watts of power. If it is in use for 2 hours per day (on average), how many kilowatt hours will it use in 30
days?
A.
1.1 x 104 kilowatt hours
B.
36 kilowatt hours
C. 18 kilowatt hours
D. 540 kilowatt hours
E.
1.1 x 106 kilowatt hours

The drag force, fd, imposed by the surrounding air on a vehicle moving with velocity v is given by fd = cdaρv 2/2 where cd is a constant called the drag coefficient, a is the projected frontal area of the vehicle, and ρ is the air density. an automobile is moving at v = 80 kilometers per hour with cd = 0.28, a = 2.3 m2, and ρ = 1.2 kg/m3.