It would be 15 greater than or equal to 14
Step-by-step explanation:
Let's look at what we know. We know that...
P=2000
r=0.04 (Change 4% to a decimal)
t=7 (25 years minus 18 years equals 7)
n=1
Since we are compounding each year, we need to use this equation: 
Now just plug the numbers in: (Answer to #1:) 
This equals 2631.86
When we round, this equals to $2,632. (Answer to #2).
diameter is 15 meters then radius is 15/2 = 7.5 meters
so the amplitude is 7.5 m and height will oscillate with amplitude 7.5 m above and below the center.
midline of the oscillation will be 7.5 m
the wheel.take 8 minutes to complete revolution then it means the height will oscillate with a period of 8 minutes