The simplest answer and the correct one is saturated. You can try this at home to see what it looks like. Take a glass and fill it to the 1/2 full mark. Make sure the water is on the coolish side. Start putting measured amounts of salt in the water. Do this until you see salt on the bottom of the glass. The solution is now saturated.
Empty the glass. Put the same amount of water in the glass but make it much warmer. Put the same amount of salt in the glass. It should not be saturated -- that is there should be no salt on the bottom.
So temperature determines saturation. But more important, you should get an idea of what saturation is.
D. As acids are highly corrosive, so it's important to wear goggles, lab coat, chemical gloves and close-toed shoes to avoid from any accident during the experiment
The total number of protons in the nucleus of strontium is different than that of the Sodium ion. This results in the electrons in the orbits to posses different energy due to the difference in electrostatic bonding between the electrons.
Due to the difference in the energy between these electrons ,the emitted/absorbed light would be at a different radiation,wavelength and colour.