How does the height of boys and girls change during puberty?

State the age at which adolescence usually begins and the age up to which it lasts.

Which is the most conspicuous change (clear visible change) in boys and girls during puberty?

Name one factor on which the height of a person depends.

A nine year old boy is 120 cm tall. If the present height of boy is 75% of his full height, calculate the full height which the boy will eventually reach at the end of growth period.