The answer is 7 (its like the only question thats easy so far lol)
15,000J/.15% = 100,000 J
If you want to check,
Multiply 100,000 by .15 and you get 15,000 J
50π m ≈ 157 m
Explanation:
100 rev/min (2π rad/rev) / (60 sec/min) = 3⅓π rad/s
d = ωrt = 3⅓π(0.50)(30) = 50π m ≈ 157 m
It can be noted that the directions west and north are perpendicular to each other. hence we can use the right angle formula for calculating total distance in these directions. Also South is just negative north. This technique is called euclidean distance norm. It is the basis of Cartesian coordinate system.
Total distance = 3.22 N + 4.75 W +1.90 S
= 1.32 N + 4.75 W
D = 
D = 4.93 Km
direction = atan(N/W) = 15.53 deg north of west