Answer:
Options d.
Explanation:
As white light from the sun is passed through a prism, it is separated into colors - red, violet, yellow, blue, green, orange, and indigo.
Dispersion is the process of the separation of visible light into its different component colors. The light waves are refracted as they enter the prism.
So, option d. is correct.
Answer:
amount of fertaliser--> the independant variable is the one being changed
The atomic number is 8
Atomic number=number of proton or number of electrons
Your answer is

but if you are looking for some explanation check description below :)
Diphosphorus trioxide formula is:

Di stands from 2 atoms of something, in this case we have 2 atoms of Phosphorus.
Trioxide means that we have 3 atoms of oxygen in this substance that's why we have:

And water is just

Unbalanced formula is:

Now we need to balance this equation
On left hand side we have 2 atoms of Phosphorus, on right hand side we have just one atom of Phosphorus, that's why we need to put 2 before

Now we need to count all atoms of oxygen and hydrogen and make it equal on both side.
So we need to put 3 on left hand side before water to make this equation balanced.
That's why correct answer is:
Answer:
T = 246 K
Explanation:
Given that,
Number of moles, n = 0.750 mol
The volume of the cylinder, V = 6850 mL = 6.85 L
Pressure of the gas, P = 2.21 atm
We need to find the temperature of the gas stored in the cylinder. We know that,
PV= nRT
Where
R is gas constant
T is temperature
So,

or
T = 246 K
So, the temperature of the gas is equal to 246 K.