18. It would be the second graph. The third graph is eliminated as the boy takes a time period to shave, which means there should be a constant point (horizontal line) right after the first incline. The first one is eliminated as the boy takes a bath which requires another constant point in the graph.
19.
C
E
D
A
B
Answer:
Step-by-step explanation:
Just plug in 20 for t:

Biased because the survey was conducted in a limited field of people aka health club which does not include other people, perhaps an unhealthy club? Or the people who are not a part of the health club? Or people who do not care about their health?
Answer:
5/7
Step-by-step explanation: