Sharks, whales, and dolphins share similar features such as body shape and the position of fins. however, sharks have gills for breathing, while whales and dolphins have lungs. these differences indicate that the organisms share a common ancestor for ?

The first space is "body structure, but their breathing structures evolved from different ancestors"

The second space is "evolved from organisms with legs"

Explanation:

I got it right on Plato.

the national environmental policy act (nepa) is a united states environmental law that promotes the enhancement of the environment and established the president's council on environmental quality (ceq). the law was enacted on january 1, 1970. to date, more than 100 nations around the world have enacted national environmental policies modeled after nepa.

c) 50% there are four chromosomes. after crossing over, 2 of the four have been changed. that means any gamete has a 2 in 4 chance or 50% chance of receiving the mutated chromosome.