Geometry

 1. (30 p.) If $$ABCD$$ is a convex quadrilateral with $$AB=200$$, $$BC=153$$, $$BD=300$$, $$\angle BAC=\angle BDC<90^{\circ}$$ and $$\angle ABD=\angle BCD$$, determine $$CD.$$

 2. (23 p.) The angle $$\angle C$$ of the isosceles triangle $$ABC$$ ($$AC = BC$$) has measure of $$106^o$$. M is a point inside the triangle such that $$\angle MAC = 7^o$$ and $$\angle MCA = 23^o$$. The measure of the $$\angle CMB$$ in degrees can be written as a fraction $$p/q$$ for relatively prime integers $$p$$ and $$q$$. Calculate $$p+q$$.

 3. (9 p.) A right circular cylinder has a diameter 12. Two plane cut the cylinder, the first perpendicular to the axis and the second at a $$45^o$$ angle to the first, so that the line of intersection of the two planes touches the cylinder at a single point. The two cuts remove a wedge from the cylinder. If $$V$$ is the volume of the wedge calculate $$V/\pi$$.

 4. (23 p.) Let $$AXYZB$$ be a convex pentagon inscribed in a semicircle with diameter $$AB$$. Suppose $$AZ-AX=6$$, $$BX-BZ=9$$, $$AY=12$$, and $$BY=5$$. Find the greatest integer not exceeding the perimeter of quadrilateral $$OXYZ$$, where $$O$$ is the midpoint of $$AB$$.

 5. (11 p.) Let $$ABCD$$ be a convex quadrilateral such that $$AB\perp BC$$, $$AC\perp CD$$, $$AB=18$$, $$BC=21$$, $$CD=14$$. Find the perimeter of $$ABCD$$.

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