help another one, my hw is due in like 20mins

Answer:
The diameter is 18 yards
Step-by-step explanation:
Diameter is 2 radius's in our case 9 plus 9 equals 18. But hey don't forget the units so it is 18 yards.
Answer:
the formular for calculating the diameter is
d=2×r(multiply 2 times the radius)
d=18 yards