Question

the band teacher seats students into groups by the instruments they play. the section labeled d is the drum section. what is the measure of the angle, d, that represents the drum section? 60° 70° 90° 110°

Explanation:

Step1: Recall semi - circle angle

A semi - circle has an angle of 180°.

Step2: Sum known angles

The sum of the known angles is $5^{\circ}+20^{\circ}+65^{\circ}+20^{\circ}=110^{\circ}$.

Step3: Calculate angle d

We know that the sum of all angles in the semi - circle is 180°. So, $d = 180^{\circ}-110^{\circ}=70^{\circ}$.

Answer:

70°