Could use some help with an explanation to these questions, thanks!

1. Of the 12 temporary employees in a certain company, 4 will be hired as permanent employees. If 5 of the 12 temporary employees are women, how many of the possible groups of 4 temporary employees consists of 3 women and 1 man?

A) 20
B) 35
C) 56
D) 70
E) 105

Don't have the answer for this one.


2. For every integer k from 1 to 10, the kth term of the sequence is given by ((-1)^k+1)*(1/2^k). If T is the sum of the first 10 terms in the sequence, then T is:

A) Greater than 2
B) Between 1 and 2
C) Between 1/2 and 1
D) Between 1/4 and 1/2
E) Less than 1/4

Answer: D


3. If n is a multiple of 5 and n = p^2*q where p and q are prime numbers, which of the following must be a multiple of 25?

A) p^2
B) q^2
C) pq
D) p^2*q^2
E) p^3*q

Answer: D


4. A certain city with a population of 132,000 is divided into 11 voting districts, and no district is to have a population that is more than 10 percent greater than the population of any other district. What is the minimum possible population that the least populated district could have?

A) 10,700
B) 10,800
C) 10,900
D) 11,000
E) 11,100

Answer: D