Answer:
this answer is 3 for b i got it right
Full circle
Circumference = 2*pi * r
Circumference = pi * d
Area = pi r * r = pi * r^2
Area = pi d^2 / 4
Half circle
Circumference = pi * r
Circumference = pi * r / 2
Area = pi r^2 / 2
Area = pi d^2/8
The answer depends on what you are looking for and what you are given. But those are the only common formulas I can think of at the moment.
#40 is $110.16 total. You have to add the sales tax to the amount of the baseball cap which comes to $13.77. Then take that amount and multiply by the number of caps. Hope this helps.