Answer: 
Step-by-step explanation:
Given
River is flowing from south to North with a velocity of 
Motor boat traverses the river from east to west at a speed of 
South component of boat velocity must compensate the river velocity in order to travel in west direction.

Answer:
A
Step-by-step explanation:
Answer:
No, Yes,Yes, No
Step-by-step explanation:
5x is false
Do the vertical line test
16. Function
17. Not
18. Not
19. Function