Is it 7.1 or something I don’t know for sure
Step-by-step explanation:
the formula to calculate a circumference is

(consider x as the diameter)
so I'll be noting the circumference as C alongside the circle's ranking
a.

b.

c.

hope I helped
We are told that f(1) = -1.5, and that f(n+1) = -2f(n).
Then: f(2) = -2f(1) = -2(-1.5) = +3 (answer)
1 liter = 1000mL
Divide 1000mL by mL per minute:
1000 / 5 = 200 minutes ( 3 hours and 20 minutes)
Putting in h(1) would get you 1, putting in h(4) would get you 5.