Circumference = 2 pi r , so
36 pi = 2 pi r
r = 36 pi / 2 pi
= 18 cm answer
Hi there!

Remember the following

Now we can easily work out the parenthesis using FOIL method.
First 2m × 2m = 4m^2
Outside 2m × -9 = -18m
Inside 2m × -9 = -18m
Last -9 × -9 = 81
Finally some simplifying

The third answer is correct.
~ Hope this helps you!
B)
It is "B" because 1.6 is how much detergent they use.
Hope this helps:)
Reciprocal means the opposite so the reciprocal of 6/5 is 5/6