1. Which relation represents a function?
a] x = 1, 1, 1, 1, 1
y = 2, 3, 4, 5, 6
b] x = 1, 2, 3, 4, 5
y = 5, 4, 3, 2, 1
c] x = 1, 2, 1, 2, 1
y = 0, 1, 2, 3, 4
d] x = -2, -1, 0, -1, -2
y = 2, 3, 4, 5, 6
2. The function f(x) varies directly with x and f(x) = 2 where x= 10
what is the value of f(x) if x= 40
a] 320
b] 45
c] 200
d] 8