The Cambrian Explosion is when diverse animals were first recorded as fossils.
This statement is true. Developing countries indeed tend to have more people in urban areas than rural areas. For example, New York City has the massive population in the state of New York, compared to its rural areas upstate.
When you combine the genotypes in the Punnet square you get :
1. EeRR
2.Eerr
3.EeRr
4.eerr
The ratio would be typical for a dihybrid cross: 9 of the individuals with both dominant traits, 3 of the individuals dominant for one trait, 3 dominant for the other trait and only one recessive for both traits.
There will be 9/16 of ebony flyes with red eyes
3-16 of ebony flies with orange eyes
3/16 of yellow flies with red eyes
1/16 of yellow flies with orange eyes