请数学大神帮忙解题。感激不尽。

flpalmbeach

What is the remainder when the positive integer n is divided by the positive integer k, where k > 1?

(1) n = (k + 1)^3

(2) k = 5
这题选A 可以解释一下吗？

If 2/5of the students at College C are business majors, what is the number of female students at College C?

(1)  2/5 of the male students at College C are business majors.

(2)  200 of the female students at College C are business majors.

这题为什么选C？

If t is a positive integer and r is the remainder when t^2+ 5t + 6 is divided by 7, what is the value of r?

(1) When t is divided by 7, the remainder is 6.

(2) When t^2 is divided by 7, the remainder is 1.

这题选A 怎么做呢？

谢谢哦