Mackenzie knows the surface area of a sphere. which explains how she can find the surface area of a hemisphere with the same radius?
a. divide the surface area of the sphere by 2, and add the area of the base of the hemisphere.
b. multiply the surface area of the sphere by 2, and add the area of the base of the hemisphere.
c. divide the volume of the sphere by 2.
d. multiply the volume of the sphere by 2.

a. Divide the surface area of the sphere by 2, and add the area of the base of the hemisphere.

Step-by-step explanation:

The surface area of a sphere is given by:

The surface area of a hemisphere with the same radius is given as :

We can see that the surface area of hemisphere is half the surface area of the sphere.

But as a sphere is a round shape but hemisphere is a hollow one. So, we will add the area of the base of hemisphere to the surface area of the hemisphere.

Therefore, the right answer is A- Divide the surface area of the sphere by 2, and add the area of the base of the hemisphere.

$53.50

step-by-step explanation:

you have to subtract the amount of money chuck earned ($72.50) by the cost of the gas for the mower ($11.25) and the new string for the trimmer he bought ($7.75).

72.50-11.25=61.25

and then subtract $61.25 by the second thing he bought (the new string for the trimmer)

61.25-7.75=53.5

so in total it's $53.50 (53 dollars and 50 cents)