Deuterium differs from Hydrogen in having:

Explanation
Deuterium, (D, or 2H), also called h eavy hydrogen. Deuterium is an isotope of hydrogen. In the simple hydrogen molecule,  there is one proton, one electron, and no neutrons, protons, electrons, and neutrons being the elementary particle s that make up the atom. ). while  Deuterium, on the other hand, is composed of one proton, one electron , and one neutron . ND11-07-2023

Explanation
As the person is 7th from the either end, implies, there are 6 persons ahead of him and 6 persons behind him as shown below. Hence, there are 13 persons in the queue.

Explanation
The given series is a square of natural number (1)^2 = 1 (2)^2 = 4 (3)^2 =9 (4)^2 = 16 (5)^2 = 25 (6)^2 = 36 (7)^2 = 42 (8)^2 = 64

Explanation
b=12, c−a=8 a2+b2=c2 ⇒b2=(c−a)(c+a) ⇒144=8×(c+a) Solving we get, c = 13 cm, a = 5cm Area of triangle =21×12cm×15cm=30cm2

Explanation
The difference between consecutive terms of the given series are respectively 5, 7, 9, 11 and 13. Clearly, 34 is a wrong number and must be replaced by (24 + 11) i.e. 35.

Explanation
James Watson is an American molecular biologist, geneticist, and zoologist. In 1953, he co-authored with Francis Crick the academic paper proposing the double helix structure of the DNA molecule.  ND13-07-2023