Of the following outer electronic configurations of atoms, the highest oxidation state is achieved by which one of them?

Among the following compounds which can be dehydrated very easily is

In a first order reaction, the concentration of the reactant decreases from 0.8 M to 0.4 M in 15 minutes. The time taken for the concentration to change from 0.1 M to 0.025 M is

Identify the correct statements regarding enzymes