If a breeder wants to introduce a disease-resistant strain, what should be the first step?

$A$ particle is moving in a circle with uniform speed $v$. In moving from a point to another diametrically opposite point:

The image formed by a convex mirror of focal length $30 \ cm$ is a quarter of the size of the object. The distance of the object from the mirror is $... \ cm$.

$CFCl_3$ is responsible for the decomposition of ozone to oxygen. Which of the following reacts with ozone to form oxygen?

$A$ diatomic gas $\left(\gamma = \frac{7}{5}\right)$ is compressed adiabatically to a volume $\frac{V_i}{32}$,where $V_i$ is its initial volume. The initial temperature of the gas is $T_i$ in Kelvin and the final temperature is $xT_i$. The value of $x$ is:

Which of the following is not a synthetic polymer?