∠EFG and ∠GFH are a linear pair, m∠EFG = 2n + 21 and m∠GFH = 4n + 15. What are m∠EFG and m∠GFH?

2: 10

step-by-step explanation:

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

b is not a step used for an equilateral triangle

step-by-step explanation:

you don't draw a line.