Answer is $506.25.
first month is $100,
second month is 100 times 1.5 which is 150.
thirst month is 150 times 1.5 which is 225.
fourth month is 225 times 1.5 which is 337.5
fifth month is 337.5 times 1.5 which is 506.25
Question a is 48 i think! because if you do 12 x how many side there are. it’s 4 so 12 x 4