If a straight line falling on two straight lines makes the interior angles on the same side of it,whose sum is $120^{\circ}$,then the two straight lines,if produced indefinitely,meet on the side on which the sum of angles is

State whether the following statement is true or false:
Only one line can pass through a single point.

Ram and Ravi have the same weight. If they each gain weight by $2\, kg$,how will their new weights be compared?

Solve the following question using an appropriate Euclid's axiom:
In the figure,we have $\angle 1 = \angle 2$ and $\angle 2 = \angle 3$. Show that $\angle 1 = \angle 3$.

Read the following statement:
An equilateral triangle is a polygon made up of three line segments out of which two line segments are equal to the third one and all its angles are $60^{\circ}$ each.
Define the terms used in this definition which you feel necessary. Are there any undefined terms in this? Can you justify that all sides and all angles are equal in an equilateral triangle?

Euclid's second axiom is: