What are the advantages of electromagnetic and magnetic surveys in mineral exploration?

1. 1 mole of anything contains 6.022x10^23 pieces  

d  

2. a  

3. c, number  

5. 1.24x10^24atoms / 6.022x10^23atoms/mole = 2moles h2 atoms  

6. fe2br3 mass = 2moles x mass fe + 3 moles x mass br  

molar mass = grams / number of moles = g/mole  

to find moles = g / molar mass  

to find mass = g = molar mass / moles

answer; /// the amount of material dissolved in a measure of liquid(concentration) the above statement is (true); /// good luck

practical process described pest part of scientific investigation.

because practical knowledge is powerful then therotical knowledge.