White moths were found in huge numbers in the city of birmingham these moths could be easy camouflage by the trees because of studying industrial development in the trees the city were convert shoot. how will this change affect the population of white moths?

It declined drastically  

Explanation:

The moths were active at night and rested  by day on white birch trees, where they were effectively camouflaged from predators.

However, as the city became more industrialized, the trees were covered with black soot from the factories.

The white moths lost their camouflage, so their population declined drastically, as their predators could now find them more easily.

the density of gold = 19.3 g/cm3

the relation between density and mass and volume is

density = mass / volume

given :

mass of gold = 13 g

density = 13g / volume = 19.3

volume = 13 /19.3 = 0.67 cm^3

thus volume of gold nugget = 0.67 cm^3