Answer:
The measure of arc EF = 41°
Explanation:
Given:
Arc DE = 73°
![\angle FED=123\°](https://img.qammunity.org/2020/formulas/mathematics/middle-school/3gap6qn0xgp0s4pw2q7r5lqyqq4p0qvy60.png)
Now, we know from central angle theorem that the measure of central angle by an arc is twice that of the angle made by the same arc at the circumference. Therefore,
![\textrm{Major Arc DGF}=2* \angle FED\\\textrm{Major Arc DGF}=2* 123\\\textrm{Major Arc DGF}=246\°](https://img.qammunity.org/2020/formulas/mathematics/middle-school/o5lf1n564oipdylmft40i9sowh5x3opvy4.png)
Now, we know that sum of all arcs on a circle is equal to 360°.
Therefore, arc DGF + arc DE + arc EF = 360°
![246+73+arc\ EF=360\\319+arc\ EF=360\\arc\ EF=360-319=41\°](https://img.qammunity.org/2020/formulas/mathematics/middle-school/ppxaecklhy1vlhj8e3mn3bv837dvht94kk.png)
Therefore, the measure of the arc EF is 41°.