Hi there!!!
So using this rule:
Area = base * height
20ft * 15ft = 300ft^2
↑ ↑
base height
HOPE IT HELPS U!!!!!!!!!
THE ANSWER IS 300 FT^2
~ TRUE BOSS
Answer is square with the side of 212 inches. It's area is 212×212 which is bigger than rectangular area.
Assuming compount interest format

for compounded per 1 year
A=future amount
P=present amount
r=rate in decimal
t=time in years
given
P=270
r=5%=0.05
the equaton is

or

for any year, 2009, is year 0, so if you wanted to input the year then

would be for t=what year it was
A.

b. 2009 to 2020
2020-2009=11 years
t=11

f(11)=461.792
about 462 cranes
A.

B. about 462
So from what I understand, you would multiply 10m by 5m for the width to get 50m squared, and multiply the 50 by 2 to get 100m for both sides of the width for the pool. Next the length. Multiply 25m by 2.5m to get 62.5m squared. Once again, mutiply it by 2 for both side lengths of the pool to get 125m. Last, add 125m and 100m to get 225m for the concrete border of the pool.