Which of the following inhibits the enzyme acetylcholinesterase?

An ideal gas is taken through the cycle $A \to B \to C \to A$,as shown in the figure. If the net heat supplied to the gas in the cycle is $5 \ J$,the work done by the gas in the process $C \to A$ is .... $J$.

If a body is projected with an angle $\theta$ to the horizontal,then

An organic compound containing $C$ and $H$ has $92.3 \%$ of carbon. Its empirical formula is:

Most of the endangered species are the victims of

$A$ charge $Q$ is divided into two charges $q$ and $Q-q$. The value of $q$ such that the force between them is maximum,is