The number of weeds found growing along the side
 number
 of a new highway each month forms the sequence whose general term is a, = (n + 1)(n +4), where n is the
 of the months. Find the number of weeds found in the fifth month, and find the total number found in the first five months.
 How many weeds were found in the fifth month? 54
 How many weeds were found during the first five months? _