The average is (time)/(number of problems)=(45/60)/20=(3/4)/20=3/80 hours per problem. In minutes, the answer would be 3/80*60=9/4 minutes per problem.
It is A'C' because when the figure is dilatted the corresponding figure has " by it.
hopes this helps :)
The answer is false due to the object is changes shape not size
.50(150)+30=$105
8(32)+12 = $268