Which of the following reagents when heated with ethyl chloride,forms ethylene?

$A$ conducting square loop of side $L$ and resistance $R$ moves in its plane with a uniform velocity $v$ perpendicular to one of its sides. $A$ magnetic induction $B$,constant in time and space,pointing perpendicular and into the plane of the loop,exists everywhere with half the loop outside the field,as shown in the figure. The induced $emf$ is

Which of the following is a bacterial domain?

Which of the following oxoacids of phosphorus has the lowest oxidation state of phosphorus?

Manganese inhibits calcium translocation in $.......$

An electron initially present in an excited state of $H$ atom is further excited to another energy level by an incident photon. It releases $10$ photons while coming back to the ground state,out of which $7$ have higher energy than the incident photon. The electron was initially present in