Iron, water, sugar, salt, nitrogen gas, and oxygen gas
Answer:
<em>The correct option is D) How is the number of frogs in Massachusetts affected by pollution</em>
Explanation:
A scientific question can be described as a question which can be answered through the scientific method of research. Based on the scientific question, a hypothesis can be formulated. For example, for the option D, the hypothesis can be 'if the pollution increases, then the number of frogs decreases.' A hypothesis is a tentative statement which can be tested through experiments. Based on these experiments, results are formulated and conclusions are drawn. The question mentioned in option D can be answered through this method hence, it is the correct option.
The longest phase of mitosis is prophase. Because the nuclear membrane disappears, Nucleolus disintegrates, and the DNA condensed to form chromosomes (each chromosome is composed of sister chromatids attached around centromere.)
