Find the length of the radius of a sphere with a surface area of 78.54 km2.
A. 5 ft
B. 15 ft
C. 10 ft
D. 2.5 ft

Question

Find the length of the radius of a sphere with a surface area of 78.54 km2.
	A.	5 ft
	B.	15 ft
	C.	10 ft
	D.	2.5 ft

turingtest · Answer

what google didn't work this time?

jamesj · Answer

$$ Surface \ Area  = 4 \pi r^2 $$
where r is the radius.

Use this formula to find the answer.

anonymous · Answer

Google is not smart enough.

turingtest · Answer

$$A=4\pi r^2$$so$$r=\sqrt{\frac{A}{4\pi}}$$so plug in the value you are given for the area A, out will come r, your answer, as James will testify

anonymous · Answer

k, thanks

turingtest · Answer

what did you get?

anonymous · Answer

well calculating things is actually hard; no ?

turingtest · Answer

It would seem

anonymous · Answer

wait, what the heck is the radius?

anonymous · Answer

The answer.

anonymous · Answer

yeah it's a heck! what the heck is that!!!

anonymous · Answer

That is what needs to be figured out. So, call it r for now.

earthcitizen · Answer

Just explain the damn thing!

anonymous · Answer

oh wait, sorry. that was a dumb question. I was looking at it backwards

anonymous · Answer

What's wrong with Google?

turingtest · Answer

your mantra:$$A=4\pi r^2$$so$$r=\sqrt{\frac{A}{4\pi}}$$

anonymous · Answer

EarthCitizen - Lot of people dedicate their time to help here. I don't think making demands on them and throwing arrogant insults is the best way to show respect and gratitude for their contributions.

anonymous · Answer

lol Mantra.

earthcitizen · Answer

whose arrongant and pompous by teasing ppl for the unfamiliarity with a topic! Focus!

turingtest · Answer

where is saifoo?
he is neglecting his modship

anonymous · Answer

I don't remember anyone making fun of people for not knowing. Nobody even makes fun of not getting it. Yes, sometimes people do expect "learning" and insist on it.

anonymous · Answer

wait, you guys.. im totally lost :-/ i need help.

anonymous · Answer

pro-tempo-re mods can't be assigned much of tasks

turingtest · Answer

Just for good measure$$A=4\pi r^2$$so$$r=\sqrt{\frac{A}{4\pi}}$$plug in the surface area (given in the problem) where the A in the formula goes. Out comes r, the answer.

earthcitizen · Answer

then tech the best way YOU CAN!

anonymous · Answer

On the contrary I find EarthCitizen a bit swanky.

earthcitizen · Answer

teach

anonymous · Answer

TuringTest: May be she needs helps in finding the square root too ?

anonymous · Answer

Surface are of sphere = 4*pi*r^2 = 78.54km^2
So, r^2 = 78.54/(4*pi)
So, r = SQRT(78.54/(4*pi))
So, r = ?

anonymous · Answer

2.5?

turingtest · Answer

Yes
Yes
Yes

earthcitizen · Answer

yep

anonymous · Answer

Yay! Good job.

anonymous · Answer

Congratz.

anonymous · Answer

oh thank god!

anonymous · Answer

Magnum opus!

anonymous · Answer

sorry you guys for being so cranky. along with math, I am also completing an essay. lots of work and multi tasking

anonymous · Answer

Apology accepted.

anonymous · Answer

We are thick skinned! Glad to see you do it.

bimbim2697 · Answer

GT CAN U HELP ME PLZ?

anonymous · Answer

thankyou. still a lot more!! have the patience?

anonymous · Answer

Well, I am also dark skinned on top!! hahahahaahaha.

anonymous · Answer

lol! I ain't dark skinned like you GT :P

earthcitizen · Answer

i see the light in U!

anonymous · Answer

First of all question is somewhat wrong!!!!!
 Radius is a quantity representing length and radius doesn't need to be written as length of the radius.
And coming to answer Surface area of sphere is 4*pi*r*r.
From that r can be found out substituting others.