Cry $II$ Ab and Cry $I$ Ab produce toxins that control:

Which of the following species has no $p\pi-p\pi$ bond but has a bond order equal to $O_2$?

During the mean life of a radioactive element,the fraction that disintegrates is

$A$ moving coil galvanometer of resistance $100 \ \Omega$ shows full-scale deflection when a current of $100 \ \mu A$ passes through it. If it is intended to show full-scale deflection when a current of $1 \ mA$ passes through it,the value of shunt resistance in ohms to be connected to the galvanometer is:

Two sound waves of slightly different frequencies propagating in the same direction produce beats due to

$\int_0^1 \sin \left(2 \tan ^{-1} \sqrt{\frac{1+x}{1-x}}\right) d x$ is equal to :