Answer:
The dark peppered moth's population increased as the use of coal increased because, since the trees were darker, it was harder for predators to see them. The light moths were easily seen and, therefore, much easier to get eaten/killed which is why their population went down.
1. The variation is the color of the moth (light vs dark).
The selection is directional selection (the trait is favorable, so it will become common among the population).
2. The peppered moth population would most likely decrease dramatically. Majority of the 95% of dark moths would get killed off since the trees are becoming light again. The light moths would be at 5% and slowly increase as the trees became lighter. Therefore the population would decrease.
3. The variation is the color of the beetle (green vs brown).
4. The brown beetle is selected for because their color is allowing them to not get eaten.
The green beetle population will decrease until there are no more.
The brown beetle population will increase until they are the only color.
: )