Ethan is buying clothes for a camping trip. A pair of hiking boots costs $96, a flannel shirt costs $33, a pair of shorts costs $17, and a light jacket costs $48. Round each amount to the nearest ten dollars to estimate of the total cost of Ethan’s purchases. A. $130
B. $150
C. $180
D. $200

answer: option a.

step-by-step explanation:

you know that the quadrilateral opqr ( a four sided figure) is inscribed in circle. this means that all its vertices are on the circle.

then, by definition, the opposite angles of the quadrilateral are supplementary, this means that the sum of their measures is 180 degrees.

you can observe in the figure that the angles ∠opq   and the angle ∠orq   are opposite, therefore:

then, can be used to d to calculate the measure of ∠opq