Answer: It becomes more dense when it freezes.
Explanation: water becomes less dense when it freezes because ice has a cage like structure.
The bug's mass is too low and the train is moving at a higher speed
The answer to your statement is TRUE!!
Answer:
Your answer is B) Mutations lead to genetic variation.
Think of it like this, when rays were first starting to develop, they probably started with only one kind, stingless. Somewhere down the line, the genes of the rays started to mutate and eventually, there were stingrays and stingless rays. Now at this point there are predators that frequently feast upon the rays, so which of the two rays are more likely to defend themselves, and get away to live long enough to reproduce and pass on their genes? The stingrays! The mutation that may have occurred millions of years ago, has determined which organisms were more fit for a changing environment.
