In which of the following is lead sulfate $(PbSO_4)$ soluble?

The correct order of $S-S$ bond length in the following oxyanions is:
$(I)$ $S_2O_4^{2-}$ $(II)$ $S_2O_5^{2-}$ $(III)$ $S_2O_6^{2-}$

Which one of the following orders presents the correct sequence of the increasing basic nature of the given oxides?

$A$ sonometer wire resonates with a given tuning fork,forming standing waves with five antinodes between the two bridges when a mass of $9 \, kg$ is suspended from the wire. When this mass is replaced by a mass $M$,the wire resonates with the same tuning fork,forming three antinodes for the same positions of the bridges. The value of $M$ is .... $kg$.

The solution of $\frac{dy}{dx} + \frac{1}{3}y = 1$ is

Suppose $E$ and $F$ are two events of a random experiment. If the probability of occurrence of $E$ is $1/5$ and the probability of occurrence of $F$ given $E$ is $1/10$,then the probability of non-occurrence of at least one of the events $E$ and $F$ is