The answer is 1.91 m
It is given:
S = 2 π r l
S = 36 m²
r = 3 m
l = ?
π = 3.14
So, let's just solve this:
36 = 2 · 3.14 · 3 · l
36 = 18.84 · l
⇒ l = 36 ÷ 18.84
⇒ l ≈ 1.91 m
I'm no expert, but considering it went down its probably a decease. (duh). I think its 77%, but I'm not very good with percentages
