Questions

Answer A is incorrect because it pertains to the processes. Answer C is incorrect because these are the five phases of a project. Answer D is incorrect because there are 39 processes, not knowledge areas.

It returns -1

The kidneys are stimulated to produce renin by a decrease in the blood pressure.

The renin-angiotensin system or RAS regulates blood pressure and fluid balance in the body. When blood volume or sodium levels in the body are low, or blood potassium is high, cells in the kidney release the enzyme, renin. Renin's primary function is therefore to eventually cause an increase in blood pressure, leading to restoration of perfusion pressure in the kidneys.

"National Volunteer Day" & "International Peace Day" are observed on 21st september every year.

Sublimation is a process when a solid changes directly into gas instead changing into liquid first. Dry ice is an example of Sublimation process because it doesn't change into liquid CO2 and directly change into gaseous CO2 when heated.

Hence, Dry ice is an example of Sublimation process. 

A Hole.

When you are digging a hole the more you take out the soil, the igger the hole becomes.