macros, functions, and command buttons
 

i need to create a macro that will call a function from a
command button. this function should be able to pull two
dates from cells on a worksheet(e4 and e7), and count the
days between the two dates, multiply the number of days
by the interest rate which is in another cell (c6), and
output the calculation to another cell on the worksheet
(d17)

how would i go about creating this macro?