Not sure about the last one, but I think the percent composition of zinc would be ~ 42.8232
Answer:
A and C represent elements while B and D represent Compounds
Explanation:
chemical elements cannot be broken down into simpler substances by any chemical reaction. While A chemical compound is a chemical substance composed of many identical molecules composed of atoms from more than one element held together by chemical bonds
I believe visible light is made from photons
Answer:
200 Joules is the explosive energy in the inside the balloon. And that is 
1 lb of TNT.
Explanation:
Volume of the balloon = V = 1 L = 
Pressure inside the balloon ,P= 200,000 Pa =
Explosive energy in the inside the balloon be E.
E = Pressure × Volume
1 lb of TNT = 
200 Joules = 
1 lb of TNT
= 1 lb of TNT
