What is the number of moles in 500l of he

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.

I think the answer is  20 moles

air

in a tire you fill a tire with air

then a couple days later you check the air pressure in the tire

hope this mark me brainliest