Which of the following is not made by quarks?

In the nuclear reaction: $X(n, \alpha) {_3Li^7}$,the term $X$ will be

If the mass number of an atom is $A = 40$ and its electron configuration is $1s^2, 2s^2, 2p^6, 3s^2, 3p^6$,the number of neutrons and protons in its nucleus will be

The particle that possesses half-integral spin is:

Pick out the correct statement from the following.

The charge density $P$ in a nucleus varies with distance $r$ from the centre of the nucleus according to the curve in the figure. Which of the following graphs correctly represents this variation?