1 is not a function. 2 is not. 3 is not. 4 and 5 are functions. 6 is not.
Answer:
Let x be a random variable representing the length of a text messaging conversation, then
P(x > 3) = 1 - P(x < 3) = 1 - P(z < (3 - 2)/0.5) = 1 - P(z < 2) = 1 - 0.97725 = 0.02275
Replace x in the equation with the given x values and solve for y:
3 + 2(4) = 11
3 + 2(5) = 13
3 + 2(9) = 21
3 + 2(10) = 23
the y values are: 11, 13, 21, 23
1 times 89 equals 89 or 89 times 1 equals 89