I believe the answer is 40
The circumference of a circle of radius
is

So, in your case, the circumference is

The circumference is actually the length of the "perimeter", so the answer to questions 1 and 2 looks the same actually
The request is to find the intersection of the two sets. By definition, the intersection of two sets is another set, composed by all the elements appearing in both sets.
In other words,
is the set of all elements that P and Q have in common.
P contains all the numbers from 0 to 9, V contains all the odd numbers between 1 and 19. So, their intersection will be the odd numbers between 0 and 9, i.e.

Answer:
15
Step-by-step explanation:
Hope this helps
Answer:
Stefan originally paid $120 for the bicycle and helmet.
He made $72 by selling them to Jin.
Step-by-step explanation:
Given that:
Selling price of bicycle = $176
Selling price of helmet = $16
Total price = 176+16 = $192
This is 160% of what Stefan paid originally.
Let,
x be the original amount paid by Stefan.
160% of x = 192

Dividing both sides by 1.6

Original amount paid by Stefan = $120
Profit = 192 - 120 = $72
Hence
Stefan originally paid $120 for the bicycle and helmet.
He made $72 by selling them to Jin.