Answer:
The answer is most likely A. Definite proportions
Explanation:
The Law of Definite proportions states that a given chemical compound always contains its component elements in fixed ratio (by mass) and does not depend on its source and method of preparation.
Exotoxin is a toxin secreted by bacteria. exotoxin can cause damage to the host by destroying cells or disrupting normal cellular metabolism
CuSO4 *5H20
In the formula of the hydrate, on the first place is the salt and on the second of water. so in ration on the first place should be salt also.
The mass of nucleons (and thus of the nucleus) is roughly 1000 times greater than that of electrons.
