Which law is followed by the different proportions of oxygen in various oxides of nitrogen?

$1.0 \ g$ of an oxide of $A$ contained $0.5 \ g$ of $A$. $4.0 \ g$ of another oxide of $A$ contained $1.6 \ g$ of $A$. The data indicate the law of:

Zinc sulfate crystals contain $22.65\%$ of zinc and $43.9\%$ of water. If it follows the law of definite proportions,how many grams of $Zn$ are required to obtain $20 \, g$ of crystals?

Which of the following sets of compounds illustrates the Law of Multiple Proportions?

Which of the following examples illustrates the Law of Multiple Proportions?

Ammonia contains $82.35\%$ nitrogen and $17.65\%$ hydrogen. Water contains $88.90\%$ oxygen and $11.10\%$ hydrogen. Nitrogen dioxide contains $63.15\%$ oxygen and $36.85\%$ nitrogen. Which law can be illustrated by the given data?