Which of the following acts as both an oxidizing agent and a reducing agent?

The $Ca^{2+}$ and $F^{-}$ ions are located in a $CaF_2$ crystal,respectively at face-centered cubic lattice points and in:

What is the meaning of the word 'ease' in French?

$A$ rod of length $20 \, cm$ is made of metal $A$. It expands by $0.075 \, cm$ when its temperature is raised from $0^{\circ}C$ to $100^{\circ}C$. Another rod of a different metal $B$ having the same length expands by $0.045 \, cm$ for the same change in temperature. $A$ third rod of the same length is composed of two parts,one of metal $A$ and the other of metal $B$. This rod expands by $0.060 \, cm$ for the same change in temperature. The portion made of metal $A$ has the length ........ $cm$.

If $f: R \rightarrow R$ is defined by $f(x) = [\frac{x}{5}]$ for $x \in R$,where $[y]$ denotes the greatest integer not exceeding $y$,then $\{f(x) : |x| < 71\}$ is equal to

The moment of inertia of a uniform semicircular disc of mass $M$ and radius $r$ about a line perpendicular to the plane of the disc passing through its center is: