It usually works well to do what the instructions tell you. Multiply each diameter by 3.14.
a) 3.14×6 cm = 18.84 cm
b) [can't read the picture]
d) 3.14×9 in = 28.26 in
e) 3.14×11 mm = 34.54 mm
Answer:
D
Step-by-step explanation:

can be simplified to

, which is an irrational number around 1.732
I hope this helps!