For a fourth-order reaction,what is the unit of $K$?

$A \rightarrow$ products ($1^{st}$ order reaction). Three sets of experiment were performed for a reaction under similar experimental conditions. Run $1 \Rightarrow 100 \ mL$ of $10 \ M$ solution of reactant $A$. Run $2 \Rightarrow 200 \ mL$ of $10 \ M$ solution of reactant $A$. Run $3 \Rightarrow 100 \ mL$ of $10 \ M$ solution of reactant $A + 100 \ mL$ of $H_2O$ added. The correct variation of rate of reaction is:

An example of a pseudo-$unimolecular$ reaction is

With the help of an example,explain what is meant by a pseudo first order reaction.

The rate law for the decomposition of hydrogen iodide is $-\frac{d[HI]}{dt}=k[HI]^2$. The units of rate constant $k$ are

For a second-order reaction where the initial concentrations of both reactants are equal,it takes $3000 \ s$ for the reaction to be $60\%$ complete. How much time (in $s$) will it take for the reaction to be $20\%$ complete?