Find the lateral surface area of the cylinder. Round to the nearest tenth if necessary.

i'm assuming that it's c.)   volcanoes built the mountains and earthquakes tore them down.

i think its 7.6

if so your welcome

answer: $53750

steps:

list the principal and interest after the n-th year:

n       principal   simple interest

1     12500     375

2     25000     750

3     37500     1125

4     50000     1500

sum: $50000     $3750

total at end of year 4: $53750