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4 years ago

Help!!!!! please!!!!!

Mathematics

1 answer:

defon4 years ago

6 0

Answer:

The answer is option b.

Step-by-step explanation:

Surface area of a sphere is 4πr²

where r is the radius

diameter = radius / 2

radius = 15 / 2 = 7.5in

Surface area = 4π(7.5)²

= 225π

<h3><u>Small </u><u>sph</u><u>ere</u></h3>

radius = 9/2 = 4.5in

Surface area = 4π(4.5)²

= 81π

Difference of the surface areas is

Surface area of big sphere - surface area of small sphere

Which is

225π - 81π

Hope this helps you.

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Applying Pythagoras formula.

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⇒ Plugging the values.

⇒ $\frac{d(h)}{dt} =\frac{2(2400+2700)(5)}{2\times 5124.45}$ ...as $\frac{d(m+w)}{dt} = 5$ ft/sec

⇒ $\frac{d(h)}{dt} =4.9761$ ft/sec

So the rate from which man and woman moving apart is 4.9761 ft/sec.

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