Questions

The atomic mass of an element depends upon the number of protons, electrons and neutrons in the atoms which make the elements.

An ionic bond is formed in between the two atoms with the transfer of electrons from an atom to the other to become stable after pairing.

The atom which has low ionization energy will give some of its electrons to get stable electronic configuration .

The Head Quarters of Archaeological Survey Of India is in New Delhi.

The Egyptian scripts is known as Hieroglyphic which means 'sacred writing' . It consisted of 24 signs, each of which stood for a single consonant. Vowels were not written. Later the Egyptian started using symbols for ideas and the total number of signs rose to about 500. The writers, who constituted an important section of society , wrote with reed pens on the leaves of a plant called 'Papyrus' from which we get the word 'paper'.

Let the missing numbers be x, y, a and b

x + y = 8 ---- (1)
a - b = 6 ---- (2)
x + a = 13 --- (3)
y + b = 8 ---- (4)

2x + a + y = 21 --- From (1 & 3)
a + y = 14 ----  From (2 & 4)

Substitute (2 & 4) in (1 & 3)

2x + 14 = 21
2x = 7
x = 3.5

From (1) ---> 3.5 + y = 8
=> y = 8 - 3.5 = 4.5

a + y = 14 => a = 14 - y = 14 - 4.5 => a = 9.5
From (4) ---- y + b = 8 => b = 8 - y = 8 - 4.5 = 3.5

Hence,
x = 3.5
y = 4.5
a = 9.5
b = 3.5

Indian Army Day is celebrated every year all over the country on 15th January.