I believe it is A and Yes
The bigger the price is on an item, the more tax you would have to pay, so both numbers increase. As for whether or not there is a line through the dots, you use a line when you could go inbetween the points. For example, with this question you can have 0.24, 0.86, or any other number as the price and it would make sense. If the question was sales tax on a certain number of shirts, well, you can't buy half a shirt so you don't need anywhere inbetween the dots.
Proportional in these kinds of problems means whether or not the line curves. If it doesn't and is a straight line, then it is proportional.
Answer:
An example below
Step-by-step explanation:
5(4a + 7(a + 2b))
First simply the inside bracket using distributive property:
7(a + 2b)
7(a) + 7(2b)
7a + 14b
5(4a + 7a + 14b)
5(11a + 14b)
Use distributive property again
5(11a) + 5(14b)
55a + 70b
Answer:
0.0158 = 1.58% probability that all of them are under 18.
Step-by-step explanation:
Probability of independent events:
If three events, A, B and C are independent, the probability of all happening is the multiplication of the probabilities of each happening, that is:

The percentage of people under the age of 18 was 23.5% in New York City, 25.8% in Chicago, and 26% in Los Angeles.
This means that 
If one person is selected from each city, what is the probability that all of them are under 18?
Since the three people are independent:

0.0158 = 1.58% probability that all of them are under 18.