Answer: No, Mary would not be able to reach the top of the car even if she stands on a stool that is 12 inches tall.
To see why, we can add up Mary's height and the height of the stool:
6 ft 8 in + 12 in = 6 ft 8 in + 1 ft = 7 ft 8 in
This means that Mary can reach up to a height of 7 ft 8 in when standing on the stool. However, the top of the car is 8 ft 4 in from the ground, which is higher than Mary can reach even with the stool. Therefore, she would not be able to reach the top of the car.
Step-by-step explanation: