The materials suitable for making electromagnets should have

According to Robert May,the global species diversity is about ...................

Which of the following $statement(s)$ is/are correct?

The engine of a jet aircraft applies a thrust force of $10^5 \ N$ during take-off and causes the plane to attain a velocity of $1 \ km/s$ in $10 \ s$. The mass of the plane is:

The Gibbs energy for the decomposition of $Al_2O_3$ at $500^o C$ is as follows :
$\frac{2}{3} Al_2O_3 \rightarrow \frac{4}{3} Al + O_2, \Delta G = +966 \ kJ \ mol^{-1}$
The potential difference needed for electrolytic reduction of $Al_2O_3$ at $500^o C$ is at least ...... $V$.

The binding energy per nucleon of ${O^{16}}$ is $7.97 \, MeV$ and that of ${O^{17}}$ is $7.75 \, MeV$. The energy (in $MeV$) required to remove a neutron from ${O^{17}}$ is