How does natural selection “drive” evolution?

Because predators and prey must learn (or adapt) new ways of survival. Deer over time have learned to be much more sensitive to the surrounding environment, therefore, a deer's predator must also adapt/evolve and learn how to beat the deer at it's own game and catch it for food. Animals must evolve/adapt to any given environment. If humans lived in Antarctica for thousands of years, we would eventually be able to withstand the cold due to evolution. People who live in the Himalayas today actually breath normally at such high altitudes whereas if someone who lives at sea level went to where the Himalayan people lived, the result could potentiality be fatal because the body has not adapted/evolved at that point to withstand minimal oxygen.

well the answer is 2!

the potatoes have high sugar concentrations and although these potatoes were different we could seethe effects that their sugar concentrations had in different environments. for example, the potatoes in sample a, were placed in pure water. this created a hypertonic environment and caused the potatoes to draw in water from its surroundings. we saw the opposite happen with the potatoes in sample b when placed in the sodium chloride solution. the potatoes in this case were in a hypotonic solution and therefore lost water to their surroundings.