Answer:
I am not sure if this is right but the answer is
The area of a circle with circumference 18π is 254.5
The answer is 9 because 5*(-3)+8+9-(-7)=9
B and C I believe .............
Answer:
a. 2,440 km
b. 
Step-by-step explanation:
a. Diameter of Mercury = 
Radius of Mercury = ½ of its diameter = 
Radius of Mercury = 
To convert the radius to ordinary number, multiply 2.44 by 1,000.
Radius of Mercury as an ordinary number = 
b. Mass of Jupiter = 
Mass of Saturn = 
Difference between mass of Jupiter and mass of Saturn =
(subtract 5.68 from 1.898 = 5.68. we would retain the largest exponent, which is raised to the lower of 27.)
