I'm not from that school but I can help you.
In order to answer this, we will set up a simple ratio as such:
1 calorie = 4.184 joules
1 kilocalorie = 1000 calories
1 kilocalorie = 4,184 joules
250 kilocalories = x joules
Cross multiplying the second and third equations, we get:
x joules = 4,184 * 250
250 kilocalories are equivalent to 1,046 kJ
Wouldn't everything fall?
Fnet = (mass) (acceleration)
= 11 kg x 3.7m/s^2
= 41 N