8. A sprinter on a school track team is running north at a velocity of 6.0 m/s. After 5.0 s, she
is running south at 4.0 m/s. Calculate the average acceleration for this interval.

The chemical reactions lab we did is typically called a "copper plating lab,  because the acid solution cleaned the pennies and made the copper look shinier;   the acid solution cleaned the paperclips and made them look like pennies;   &   the copper from the pennies was removed, and then added to the paperclips. 

The density of the block of iron is lees than the density of mercury but the density of the block of iron is greater than the density of water