Answer: 4, -4
Step-by-step explanation:
I believe that; A function is {A) sometimes} a relation.
<span>circumference = 2 π r
138.16 = 2 π r
138.16/2π = 2π/2π r
21.98884694 =r
D</span><span>iameter = r X 2
</span>Diameter = <span><span>21.98884694</span> X 2</span>
Diameter = 43.97769388
<em>f(d)=86,400·d</em>
if you set 1 day (d=1) you get f(1)=86,400 sec
if you set 1 day (d=2) you get f(2)=172,800 sec
...etc.