There is approximately 2.54 cm that equals to 1 inch. So your closet answer would be the first choice. :)
For Blake:
3 boxes at a distance of 10 meters each, each box weighs 20 N
Work done by Blake = 3 * 10m * 20N
= 600 J
Power = 600 J/ 2 min
= 300 J/min
For Sandra:
4 boxes, 15 N each at a distance of 12 meters each.
Work done by Sandra = 4 * 15 N *12m
= 720 J
Power = 720 J/ 4 min
= 180 J/min
Blake does less work than Sandra.
Blake's power is more than Sandra's.
Use Force=Mass x Acceleration (newtons second law states force is directly proportional to the acceleration) so you can say that the force is negative and solve for Acceleration.
