A quarter-circle DEF has rectangle ABCD inscribed in it, If DC =4 and CF = 3, find the length of AC. C3F A jeweler has 13 chains of 5 links each. He wants to combine them into a long chain by cutting and welding the fewest number of links. How many different links must be cut and welded? Segments AB and BC are diagonals on faces of the same cube. What is the angle ABC through the cube in degrees? B You want to put a stake every metre around the perimeter of a square plot that measures 100 metres on every side. How many stakes will you need? In the given figure, what is the sum of the angles at A, B, C. D and E? A E- (Hint: what is the sum of the angles in a triangle?) In 1939 a hamburger sold for 5, but a worker would only earn 30/h. If in a later year, a hamburger sells for 85, how much would the worker earn if earnings went up at the same rate? B.