
Actually Welcome to the Concept of the areas.
Since we know that, radius = diameter /2
here, => d = 2r ,
hence we use the formula as,
A = πr^2 ,
here option d.) is correct.
Answer:

Step-by-step explanation:
when multiplying exponents, as long as the base is the same, you add the power. 
Answer:5.5%
Step-by-step explanation:
Answer:
261.75
Step-by-step explanation:
volume= Length x width x height
hence
8.5 x 5 x 5.1
all are in inches so your answer will be in inches :)