How many triangles can be drawn having its angles as $45^{\circ}, 64^{\circ}$ and $72^{\circ}$? Give reason for your answer.

Measure of each exterior angle of an equilateral triangle is $\ldots \ldots \ldots$ (in $^{\circ}$)

In $\Delta ABC$,if $\angle A = \angle B + \angle C$,then $\angle A = \ldots$ (in $^{\circ}$)

$ABC$ is a triangle. Locate a point in the interior of $\Delta ABC$ which is equidistant from all the vertices of $\Delta ABC$.

In $\Delta ABC$,$AB = AC$ and $\angle C = 75^{\circ}$,then find $\angle B$. (in $^{\circ}$)

In $\Delta ABC$,$AD$ is a median and $AM$ is an altitude. The side $BA$ of $\Delta ABC$ is produced to any point $E$,so that $AB = AE$. If $BC = 16\, cm$ and $AM = 8\, cm$,then find the area of $\Delta EBD$ in $cm^2$.