$A$ statement that needs a proof is called a........

$A$ surface is that which has $\ldots \ldots \ldots$ only.

Solve the following question using the appropriate Euclid's axiom:
In the figure,we have $BX = \frac{1}{2} AB$,$BY = \frac{1}{2} BC$ and $AB = BC$.
Show that $BX = BY$.

Write whether the following statement is True or False. Justify your answer.
If a quantity $B$ is a part of another quantity $A$,then $A$ can be written as the sum of $B$ and some third quantity $C$.

The number of dimensions a surface has is:

Solve the following question using an appropriate Euclid's axiom:
In the figure,we have $\angle ABC = \angle ACB$ and $\angle 3 = \angle 4$. Show that $\angle 1 = \angle 2$.