Answer: a star expels most of its outer material until only the hot core remains, which then settles down to become a young a white dwarf
Explanation:
The statement that is a well-written hypothesis about DDT and its effects on the environment is as follows: If DDT levels in the environment increase, then the number of predatory birds will decrease (option B).
<h3>What is an hypothesis?</h3>
Hypothesis is a tentative conjecture explaining an observation, phenomenon or scientific problem that can be tested by further observation, investigation or experimentation.
Hypothesis is widely regarded as an educated guess because it predicts the outcome of an experiment and can be tested to either be true or false.
A hypothesis is usually written as an IF, THEN statement.
Therefore, the statement that is a well-written hypothesis about DDT and its effects on the environment is as follows: If DDT levels in the environment increase, then the number of predatory birds will decrease.
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A stem cell is an extraordinary, early stage, unspecified cell that has the potential to develop into a number of specialized cell types.
there important because they can replace cells that have been lost or damaged