Question - a grapefruit is approximately spherical. jane cuts the grapefruit in half and determines that the circumference of the resulting hemisphere is 12π centimeters. what is the surface area of one-half of the cut grapefruit?
a) 72π cm2
b) 108π cm2
c) 180π cm2
d) 432π cm2

  B)  108π cm^2

Step-by-step explanation:

We assume the circumference measurement is the same as it would have been before the fruit was cut. In that case, the radius is found from ...

  C = 2πr . . . . . . . . . formula relating circumference and radius

  12π cm = 2πr . . . . substitute given information

  6 cm = r . . . . . . divide by 2π

The surface area of a hemisphere is 3 times the area of the circular face:

  S = 3πr^2

  S = 3π(6 cm)^2 = 108π cm^2

The surface area of the grapefruit half is 108π cm^2.

B) 108π cm2

Step-by-step explanation:

If a grapefruit is approximately spherical and Jane cuts the grapefruit in half and determines that the circumference of the resulting hemisphere is 12π centimeters, the surface area of one-half of the cut grapefruit is 108π cm2.

Formula: 2πr

S = 3π(6 cm)^2

step-by-step explanation:

12: 00 p.m. to 7: 00 p.m. is a total of 7 hours.

4: 00 p.m. to 7: 00 p.m. is a total of 3 hours.

this means that from 4: 00 p.m to 7: 00 p.m. this represents 3/7 of what was lost from 12: 00 p.m. to 7: 00 p.m.

after knowing this, after doing 11,600 - 6,800 = 4,800

4,800 represents 3/7 of what was lost for 7 hours.

we then divide 4,800 by 3 which gets 1,600.

because we know that 1,600 represents 1/7 of how much water was lost, we just have to multiply by 7, which gets 11,200.   after adding 11,200 to how much water was left at 7: 00 p.m. which was 6,800. 11,200 + 6,800 = 18,000

this means that the pool originally had 18,000 gallons in the pool.

you can also check your work by doing 18,000 - 4(1600), which becomes           1800 - 6400 which gets you 11,600.

answer: i realy don't get it that much can you me figer it out pleas you

step-by-step explanation: