Match List - I (Experiment performed) with List - II (Phenomena discovered/associated) and select the correct option from the options given below the lists :

List - I		List - II
(a)	Davisson and Germer Experiment	(i)	Wave nature of electrons
(b)	Millikan’s oil drop experiment	(ii)	Charge of an electron
(c)	Rutherford experiment	(iii)	Quantisation of energy levels
(d)	Franck - Hertz experiment	(iv)	Existence of nucleus

A piece of wood from a recently cut tree shows 20 decays per minute. A wooden piece of same size placed in a museum (obtained from a tree cut many years back) shows 2 decays per minute. If half life of C¹⁴ is 5730 years, then age of the wooden piece placed in the museum is approximately :

Two radioactive substances A and B of mass numbers 200 and 212 respectively, shows spontaneous $\alpha$-decay with same $Q$ value of 1 MeV . The ratio of energies of $\alpha$-rays produced by A and B is $\_\_\_\_$ .

The energy released if hydrogen atoms are combined to form ${ }_2^4 \mathrm{He}$ is $\_\_\_\_$ MeV .

(Take binding energies per nucleon of ${ }_1^2 \mathrm{H}$ and ${ }_2^4 \mathrm{He}$ as 1.1 MeV and 7.2 MeV , respectively)