Answer:
115
Step-by-step explanation:
angle DEF is an inscribed angle and arc DF is the arc it intercepts
if you didn't know an inscribed angle is equal to half the measure of the arc it intercepts
Hence angle DEF = 1/2 of arc DF
If arc DF = 230 then angle DEF = half of 230 or 230/2
230/2=115
Hence angle DEF = 115
