Bunuel
SOLUTION
If S is a set of four numbers w, x, y, and z, is the range of the numbers in S greater than 2 ?
(1) w - z > 2. The range of a set is the difference between the largest and the smallest elements of the set, since the difference of some particular two numbers are already more than 2 then the the range must also be more than 2. Sufficient.
(2) z is the least number in S --> just says that from four unknowns z is the smallest one (obviously one of the unknowns would be the smallest one, what difference does it make to know that it's z?). Not sufficient.
Answer: A.
What if the numbers are negative though?-> If w = (-2), z = (-4), the statement would remain true [(-2)-(-4)]=6; however, the range would be 2. Therefore, the statement would be insufficient.
I'd appreciate your help 🙏
-2 - (-4) = -2 + 4 = 2, not 6. So, those values of w and z do not satisfy the first statement.