Biolistics (gene gun) is suitable for

$A$ liquid cools from $50^{\circ}C$ to $45^{\circ}C$ in $5 \ minutes$ and from $45^{\circ}C$ to $41.5^{\circ}C$ in the next $5 \ minutes$. The temperature of the surrounding is ......... $^{\circ}C$.

Four numbers are chosen at random from $\{1, 2, 3, \ldots, 40\}$. The probability that they are not consecutive is:

For all real $x$,the minimum value of the function $f(x)=\frac{1-x+x^2}{1+x+x^2}$ is

Which one of the following is most effective in causing the coagulation of an $As_2S_3$ sol?

If $a \sin^2 \theta + b \cos^2 \theta = c$,then $\tan^2 \theta$ is equal to