Answer:
Step-by-step explanation:
2.52
The option C) y = 15/x
a) y = 15 x is an example of direct variation, with proportionality constant = 15
b) is an example of linear variation (it is the equation of a straight line that does not pass through the origin)
c) y = 15/x => y*x = 15 = constant which is the characteristic of an inverse relation
d) y = x/15 is an example of an inverse relation, with proportion constant = 1/15
Answer:

multiply either sides by 3:

divide either sides by πr² :

Answer:
38 mpg
Step-by-step explanation:
Initial efficiency = 39 mpg
Initial speed = 40 mph
Final speed = 50 mph
The efficiency drop between 40 mph and 50 mph is given by:

The total efficiency drop from 40 to 50 mph is:

Therefore, the efficiency at 50 mph is:

I think it's A. I can't really see the graphs clearly. It's the one that crosses at (15,2)