Answer:
b
Step-by-step explanation:
I Think B is the right answer
Answer: a
Step-by-step explanation: Because……….
Answer:
a=3,b=5
Step-by-step explanation:

so as you got it:

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
More than 2 ... there is a right and a obtuse i think