1.0<x<1. Which must be true?
I. x^9 < x^7
II.x^7+x^5 < x^6+x^4
III. x^7-x^5 < x^6-x^4
2. A football team average x points (the mean) in the first n games, scored y points in the next game, and z points in the one after that . The mean of the n+2 is
A.(x+y+z) / (n+2)
B. (nxyz) / (n+2)
C. (nx+y+z) / (n+2)
D.x + (y+x)/2
E.(nx+yz)/n+2
3.The postage in country X is 50 gruff for the first ounce and 22 gruff for each additional ounce. A half-pound letter mailed in country X cost how many gruff?
4.Two sides of a triangle are 4 and 7. If the sides are integers, the product of the smallest possible perimeter and largest possible perimeter is
5.J, K, M are three consecutive odd integers, with j < k < m. Which is true?
l : m - j =4
II: jk +jm+ km + 1 is even
III:(j + k + m) / 3 is an integer
6. The sum of the three smallest primes than 30 is
A. 99
B. 109
C. 111
D. 115
E. 131