Rainmaker Drains Incurs a $35 Cost Each Time It Sells

Rainmaker Drains incurs a $35 cost each time it sells securities. The firm needs $128,000 a year for transaction purposes. As a routine, Rainmaker sells securities every time the balance in the account
Declines to $1,000. The applicable interest rate is 3.5%. What is the target cash balance according
To the BAT theory?

A) $5,600
B) $9,817
C) $11,314
D) $13,500
E) $16,000