Statement (A) : The angles in the same segment of a circle are equal.

Statement (B) :  The angle in a semi circle is $90°$

Statement (A) is true

$\overline{)ADB}$ and $\overline{)ACB}$ are angles in the same segment with respect to chord $\overline{AB}$.

But by a theorem, the angle made by a chord at the centre is double the angle at the remaining circle.

$\therefore$$\overline{)AOB}=2\overline{)ACB}$

Similarly $\overline{)AOB}=2\overline{)ADB}$

$\overline{)ACB}=\overline{)ADB}$

(or)

Angles in the same segment are equal.

Statement (B) is true.

$AB$ is diameter

$\overline{)AOB}=180°$

$\overline{)AOB}$ is angle made by $\stackrel{⏜}{A\times B}$ at the centre and $C$ is a point on the remaining circle

$\therefore$$\overline{)AOB}=2\overline{)ACB}$

$180°=2\overline{)ACB}$

$\overline{)ACB}=\frac{180°}{2}=90°$

$\therefore$ angle in a semicircle is $90°$