Answer:
A. Compounds contain fixed ratios of different elements.
Explanation:
Water always has this 2:1 ratio of hydrogen to oxygen. Like water, all compounds consist of a fixed ratio of elements. It doesn't matter how much or how little of a compound there is. It always has the same composition.
The diaphragm is the primary muscle used in the process of inspiration, or inhalation
D; because the cells dna is not in the nucleus
