Answer:
20 moles
Explanation:
The important thing to realize here is that you're working under STP conditions, which implies that you can use the molar volume of a gas at STP to find how many moles of helium will occupy that volume.
How emotions affects the quality of paints
X-ray radiation can be deadly but its only deadly in large amounts when you get an x-ray it is only for a picture. Gamma radiation is the most harmful radiation as it penetrates everything and gives off deadly radiation and it isn't very common.