Easy question! chemistry - ! i give - it's the picture - question 4

The key to answering this question is to realize that you have two polyhedrons combined to form one thus the overall volume would be equal to the sum of the two polyhedron.

Total volume= (volume of prism) + (volume of cuboid)

a) Volume of cuboid ()= 
      l   = 13ft
      w = 18ft
      h =  21ft
: .  = 13ft * 18 ft * 21ft
                              = 4914

b) Volume of Prism () =  
      b  = 18ft
      h  = 16ft
      H = 13ft
: . = 
                              = 1872

Thus Overall Volume = 6786
    

You use the atomic number to find out how many protons and neutrons there are in the atom. you use the atomic mass to find out how many protons and electrons there are in the atom.