Alock has 5 buttons. the lock is opened by pushing two buttons simultaneously and then by pushing one button alone. how many combinations are possible?

There are 5 choose 2 options for pushing two buttons simultaneously and then 5 options for pushing one button alone

5 choose 2 is 5!/(3!*2!) = 10

10*5 = 50 different combinations

i think it's either c or d

step-by-step explanation: the entire question is extremely odd. 04 obviously refers to the interest rate. honestly i will say the answer is c. because the (2 x 12) part would mean it's compounded semiannually. i'll say choose c.