Problem Set A In problems 1-4, draw your own diagram and write "Given:" and "Prove:" statements in terms of your diagram. Do not write a proof. 1 Given: An isosceles triangle and the median to the base Prove: The median is the perpendicular bisector of the base. (This sentence contains two conclusions- "the median is per- pendicular to the base" and "the median bisects the base.")

47. The measure, in degrees, of each interior angle of a regular polygon with \( n \) sides is given by \( \frac{(n-2) \mid 80}{n} \). What is the sum of the measures of the interior angles of a regular octagon?

2 complementary angles have the sum of ............... \( 360^{\circ} \) B. \( 90^{\circ} \) C. \( 180^{\circ} \) D. \( 60^{\circ} \)

50. Ten distinct lines lie in the same plane. No pair of these lines is parallel to each other, and no more than two of the lines intersect at any one point. How many poins lie on more than one of these ten lines? (A) 10 (B) 36 (D) 45 (D) 55 (E) 100

50. Ten distinct lines lie in the same plane. No pair of these lines is parallel to each other, and no more than two of the lines intersect at any one point. How many points lie on more than one of these ten lines? (A) 10 (B) 36 (C) 45 (D) 55 (E) 100

Calcola la lunghezza di una circoner tro 8 cm , approssimando \( \pi \) ai centesimi.