1st Person, 2nd Person, 3rd Person “Singular-Plural” Concept#!#Sentence

A body undergoes a displacement of 3 m in the 1st second, 4 m in the 2nd second, 5 in the 3rd second and so on. The body is moving with a/an

Find out of 1st,2nd and 3rd coordination number for an atom located at the corner in a simple cubic unit cell

If represents 2 persons, then represents _____ persons.