Biochemical Oxygen Demand (BOD) value can be a measure of water pollution caused by the organic matter. Which of the following statements is correct ?

The number of P $$-$$ O bonds in P₄O₆ is :

In KO₂, the nature of oxygen species and the oxydation state of oxygen atom are, respectively :

For a first order reaction, A $$ \to $$ P, t_1/2 (half-life) is 10 days The time required for $${1 \over 4}$$^th conversion of A (in days) is : (ln 2 = 0.693,    ln 3 = 1.1)