Calculating Buoyant Force on a Helium-Filled Balloon

[amjber2]

buoyant forces

I was having trouble with this problem. please let me know how to approach this. thanks.

An empty rubber balloon has a mass of 0.0135 kg. The balloon is filled with helium at a density of 0.181 kg/m3. At this density the balloon is spherical with a radius of 0.400 m. If the filled balloon is fastened to a vertical line, what is the tension in the line?

 

[gunblaze]

You should show some of ur workings b4 we can help. Alright, just a little clue to get u started. Upthrust- weight= tension of string.