Answer:
[tex]r=20.1[/tex]
Step-by-step explanation
[tex]C=\pi d[/tex]
Green car circumfrence = 126 feet
Plug in numbers
[tex]126=3.14d[/tex]
Divide both sides by 3.14
[tex]\frac{126}{3.14} = 40.12...[/tex]
Divide diameter by 2 to find radius
[tex]\frac{40.1}{2} = 20.05[/tex]
round up to [tex]20.1[/tex]