The number of two digits which is such that, the sum of the digits is 12 and the digit in the unit
place is three times the digit in tens place is:
a. 39
b. 40
c. 41
d. 42​

Einstein office equipment has a rental plan for office machines. a fax machine that lists for $722.98 can be rented for 22% of the price annually. the state imposes a usage charge of 3.2%. if stephen hawking travel decides to rent the fax machine, what will its total monthly rental charge be?