Sink or float: a table of densities

Four objects are weighed and their volumes are measured. You will find the density of each, the ones that float in water, and the densest one.

The idea. $d = \dfrac{m}{V}$. An object floats in water when its density is less than $1.00\ \text{g/cm}^3$.

Your tasks.

1. Make density, a dictionary from each name to its density in $\text{g/cm}^3$, rounded to 2 places.
2. Make floaters, the names of the objects that float, in the order of the list.
3. Set densest to the name of the densest object.