C

Find the sum of all the roots of the equation $||1-x|-2|=1$ for $x\in (1;\mathrm{\infty })$.

The 3D printer prints a solid $5$ centimetre cube in $2$ hours. The printer can print the cube with the maximum edge length of $20\mathrm{cm}$. Suppose the printing time is directly proportional to the cube volume. Choose the function that describes the dependence of the number $n$ of cubes printed in $1$ day on the printed cube edge length $a$, which is specified in centimetres. Neglect time needed for using the printer.

Choose the function that describes the dependence of a cube volume $V$ on the length of its space diagonal $u$.

Find all the values of the real parameter $p$ such that $f(x)=(p-2)x^2+px+2$ has a maximum.