Answer : The volume of liquid is 420 mL.
Explanation :
Density : The mass per unit volume of a substance is known as density.
Formula used:

As we are given:
Density of mercury = 13.5 g/mL
Mass = 12.5 pounds
First we have to convert mass of sample from pound to gram.
Conversion used:
As, 1 pound = 453.6 g
So, 12.5 pounds = 453.6 × 12.5 g = 5670 g
Now we have to calculate the volume of liquid.

Now putting all the given values in this formula, we get:

Volume = 420 mL
Therefore, the volume of liquid is 420 mL.
To answer the problem above first we need to find the difference of molar mass of NI3 from I2, 394.71 g/mol - 253.80 g/mol = 140.91 g/mol. Knowing the molar mass of the difference of NI3 from I2, in equation mass (g) / moles (mol) = molar mass, then we substitute. 3.58g / moles = 140.91 g/mol.
moles = 3.58 / 140.91 = 0.025 moles.
Nuclear Fusion is the answer to the question who posted.
Given equation:
P + O2 → P2O5
In order for the equation to be balanced, the stoichiometry of the atoms of one kind on the reactant side must be equal to that on the product
Reactants Products
P = 1 P = 2
O = 2 O = 5
The balanced equation would be:
4P + 5O2 → 2P2O5
Reactants Products
P = 4 P = 4
O = 10 O = 10
Ans: D)