Answer:
Step-by-step explanation:
External angles tangent to a circle such as this measure 1/2 of the difference of their intercepted arcs :
( ( 360 - 105) - 105 ) /2 = angle E = 75 degrees
Another way: EFCD is a quadrilateral whose internal angles sum to 360
degrees....the tangent angles at F and D are 90 degrees each....so
E + F + C + D = 360
E + 90 + 105 + 90 = 360
E = 75 degrees