Pennies made after 1982 are made primarily of one element coated with a thin layer of copper that gives it the
appearance of pure copper. Use the evidence from your
experimental results and the table of densities to identify
which element might make up most of a penny.

answer: the rate of diffusion increases with increase in temperature.

increase in temperature, increases the molecular/particles speed (kinetic energy. diffusion means movement of particles through the material.

generally, the heavier the particle the more it interacts with the environment and more the temperature matters. so higher temperature results in higher diffusion.

what is the question here. i think you messed up.