An Average of the masses of all the isotopes that occur in nature for an element is the?

Which uses electromagnetic radiation to discover the properties and composition of bodies in space? space probe space station space shuttle space observatory

Margaret wants to make an orange flavored drink by stirring powdered drink mix into a glass of water. she doesn't like drinks that have small clumps of powdered solid in them, so she wants the drink to be a perfect solution. what factors should margaret not consider when deciding how much powder to add to her glass of water?

Acontainer holds 35.8 moles of gas under 10.0 atm of pressure at 70.0 c. what is the volume of the container?