A

A body is deformed continuously in a machine press. The density $\rho$ is inversely proportional to the volume $V$ of the body, i.e. there exists a constant $k$ such that $$\rho =\frac{k}{V}.$$ Find the constant $k$ (including the correct unit) if it is known that the density was $\rho =25\frac{\mathrm{kg}}{{\mathrm{m}}^3}$ when the body had volume $V=2{\mathrm{dm}}^3$.

Identify a function which is decreasing on $(-\mathrm{\infty };1)$.

In the following list identify an increasing function.

Consider a function $$f(x)=\frac{-3}{x}$$ defined on the domain $\mathrm{Dom}(f)=\mathbb{R}\setminus \{-1.0\}$. Find the range of this function.