How much space do 2x10 22 copper pennies take up

Iknow #2 is d. i just need to know why

If a plot weight (in g) vs. volume (in ml) for a metal gave the equation y= 13.41x and r^2=0.9981 what is the density of the metal?

Consider the equilibrium system: 2icl(s) ⇄ i2(s) + cl2(g) which of the following changes will increase the total amount of of cl2 that can be produced? all of the listed answers are correct decreasing the volume of the container removing the cl2 as it is formed adding more icl(s) removing some of the i2(s)