ANSWERS: 1

The question omits a definition of theta  is it angle PRQ at point R which is the vertex of the isosceles triangle below the semicircle? As I understand your description the semicircle is fixed in size so A(theta) is constant. As theta approaches zero, the triangle below the semicircle grows longer & longer (i.e., PR and QR grow in length) so its area B(theta) approaches infinity. Therefore lim(theta>zero) of A/B approaches zero.
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