Answer:
5. D
7. B
9. A
Explanation:
5.
The probability of an event happening is a number from 0 to 1 with the following meaning:
probability of event equals:
0 - event will definitely not happen
1 - event will definitely happen
0.5 - event is as likely to happen as it is likely to not happen
From 0 - 0.5 - event is more likely to not happen.
From 0.5 - 1 - event is more likely to happen.
Here, all numbers are 0, 1 or a number in between 0 and 1, so all are possible probabilities.
Answer: D
7.
3y × 1/y + 6y² + y + 4 =
= 3 + 6y² + y + 4
= 6y² + y + 7
The constant term is 7.
Answer: B
9.
The ratio is 7:4.
One part is x.
The other part is x + 20.
Since x + 20 > x, then x + 20 corresponds to 7 in the ratio, and x corresponds to 4 in the ratio.
(x + 20)/x = 7/4
Answer: A.