The initial setting of cement is primarily due to which of the following?

Which part of the world has a high density of organisms?

Which of the following elements does not form a monoxide?

If $f(x) = \frac{x}{1+|x|}$, for $x \in \mathbb{R}$, then $f^{\prime}(0)$ is equal to :

The shortest distance between the line $y - x = 1$ and the curve $x = y^2$ is:

While a collector to emitter voltage is constant in a transistor,the collector current changes by $8.2 ~mA$ when the emitter current changes by $8.3 ~mA$. The value of forward current ratio is