Answer: b) {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}
Explanation: We simply list all the numeric single digits from 0 to 9. We'll leave out the asterisk and pound sign as they aren't numeric digits.
1.6 -1.6 +1.6 is the following
The completed factor is (7x+2) (x+5)