Answer:
495 combinations of 4 students can be selected.
Step-by-step explanation:
The order of the students in the sample is not important. So we use the combinations formula to solve this question.
Combinations formula:
is the number of different combinations of x objects from a set of n elements, given by the following formula.

How many combination of random samples of 4 students can be selected?
4 from a set of 12. So

495 combinations of 4 students can be selected.
I believe the answer is B because you have to do the Vertical Line Test.<span />
Answer:
The answer is just 1 and 3.
Step-by-step explanation:
To understand this problem, you must think of what whole numbers actually are.
Whole numbers consist of Positive integers and Zero.
Positive integers include 1, 2, 3, 4, 5, 6, ... etc
Zero is 0
The reason
isn't a whole number is because that fraction doesn't reduce any further and does not yield a whole number.