A circle is circumscribed around a quadrilateral, and the quadrilateral is ABCD, What is the value of y when angle B is 75 degrees?	Choose the correct choice from the following answers.
A) 75  B) 95  C) 105  D) 115  E) 135
An inscribed angle is an angle in a circle composed of two chords with a common endpoint, that is, an angle with its vertex on the circle. In this problem, all four lettered angles are inscribed angles.   An inscribed angle necessarily opens to intersect an arc (the technical word is to subtend an arc). The Inscribed Angle Theorem said that the measure of an inscribed angle is always half the measure of the arc it intersects, or subtends.   angle B = 75 degrees   Thus,   arc ADC = 150 degrees   A whole circle has 360 degrees of arc, so arc ABC should be the rest of the circle.   arc ABC = 360 - 150= 
<gadget id="calculator">360 - 150</gadget>
<output>210</output>
210 degrees   The angle that intersects this arc, angle D, should have half this measure.   angle D= y = 210/2= 
<gadget id="calculator">210/2</gadget>
<output>105</output>
105 degrees   Answer=(105)
<result>C</result>
A circle is circumscribed around a quadrilateral, and the quadrilateral is ABCD, What is the value of y when angle B is 75 degrees?