Answer:
459.6J
Explanation:
Given parameters:
Angle of pull  = 40°
Force applied  = 30N
Distance moved = 20m
Unknown:
Work done by Kraig  = ?
Solution:
To solve this problem;
  Work done  = F x dcosФ
d is the distance
F is the force
Ф is the angle given
 Work done  = 30 x 20cos40°  = 459.6J