How many cases are there in the age group 40- 45? 

Hydrogen contains one valence electron in its valence shell and thus, its valency is one. Therefore, hydrogen resembles alkali metals (group 1 elements) as they also contain one electron in...

Answer is (B) 25 – 30

There are 24 cases in the age group of 0 – 05.

D) First Axiom

Correct option is (A) x = 4y Given that age of x is 4 times of the age of y. \(\therefore\) x = 4y will represent the information.

C) (x + 5) years

Correct option is  B) 15 years

Correct option is (D) none Let Ramu's present age be x years. \(\therefore\) Ramu's age before 4 years = (x - 4) years Ramu's age after 12 years = (x + 12) years \(\therefore\) x+12 = 3(x-4) \(\Rightarrow\) x+12...