Suppose that an intermixed sequence of push and pop operations are performed on a LIFO stack. The pushes push the numbers 0 through 9 in order; the pops print out the return value. For example"push(0); pop(); push(1)" and "push(0); push(1); pop()" are possible, but "push(1); push(0); pop()" is not possible, because 1 and 0 are out of order. Which of the following output sequence(s) could occur? Select all that are possible.
a) 12543 609 8 7 0
b) 01564 37928
c) 6543210789
d) 02416 75983
e) 46 8 75 32 901