A sledge hammer weighs 18 pounds on earth, and 4 pounds on Namar
Divide 18 with 4
18/4 = 4.5
Ratio of Earth/Namar: 4.5/1
We are solving for an 80 pound earthling.
Divide 80 with 4.5
80/4.5 = 17.778
Round. Because 7 is greater than 5, round up.
18, or C) is your answer
hope this helps