Which number is a prime number 14,13,21,33 ?

A prime number means that the number is only divisible by one and itself. 

14 is a multiple of 2 and 7, so 14 wouldn't be it.

21 is a multiple of 3 and 7, so 21 wouldn't be it.

33 is a multiple of 3 and 11, so 33 wouldn't be it.

13 is only divisible by itself because no number can be multiplied to get 13.

So the correct answer is : 13 is the prime number.

The answer you are looking for would be B. 13.

Prime numbers are numbers that are not divisible by any numbers except 1 and itself. All even numbers (except 2) are divisible by 2, therefore eliminating 14.
21 and 33 are both divisible by 3 (21/3 = 7 and 33/3 = 11). Thus making 13 the prime number.

I hope this helps!

I’d say letter a..

In all honesty, there really is no “work” per say to show. mainly it’s just using the process of elimination. the question is asking which domain(s) would be the most appropriate for the function c(n). n is the number of observed vehicles so right away, 1, 2, and 3 can be eliminated.why? 1, 2 start in the negatives and therefore it is impossible to observe negative cars. so, #4 would be the best answer to the given problem.