Which part of the human brain is concerned with the regulation of body temperature?

What is the probability of a couple having four sons?

If the circle $x^2+y^2+8x-4y+c=0$ touches the circle $x^2+y^2+2x+4y-11=0$ externally and cuts the circle $x^2+y^2-6x+8y+k=0$ orthogonally,then $k=$

Water rises in a capillary tube of radius $r$ to a height $h$. The mass of water in the capillary is $m$. What will be the mass of water that rises in a capillary tube of radius $\frac{r}{3}$?

In the isoelectronic series of metal carbonyls,the $CO$ bond strength is expected to increase in the order:

$\int_2^3 \frac{dx}{x^2-x}$ is equal to