Answer:
Well all even numbers between 0 and 8 are,
2, 4, 6, 8
Meaning if the button is pressed 4 times 2, 4, 6, or 8 will be outputted.
Answer:
largest 4 digit number × largest 3 digit number
=9999 × 999
(10000-1)×(1000-1) = (a-b)(c-b)= ac-ab-bc+b^2
10000000-10000-1000+1 = 9989001