Masirah Inc., an escrow agent, has provided the following data concerning its office expenses: Escrows Office Completed Expenses 01.01.2021 108 8542 01.02.2021 83 8138 01.03.2021 103 8 459 01.04.2021 91 8 260 01.05.2021 64 7792 01.06.2021 102 8450 01.07.2021 50 7536 01.08.2021 57 7691 01.09.2021 30 7076 Management believes that office expense is a mixed cost that depends on the number of escrows completed. Note: Real estate purchases usually involve the services of an escrow agent that holds funds and prepares documents to complete the transaction. Using the high-low method, the estimate of the fixed component of office expense per month is closest to: a. $6,692 b. $7,376 c. $6,985 d. $8,064 e. $6,512