1. If two adjacent sides of a parallelogram are 10 cm and 20 cm and the distance between the shorter sides is 16 cm, calculate the distance (in cm) between the longer sides.   Hint Hint       2. The longer diagonal of a four-sided playground is 100 m. If the lengths of the perpendiculars from the opposite vertices to this diagonal are 11.2 m and 18.8 m respectively, calculate the area (in m2) of the playground.   Hint       3. Find the area (in cm2) of a parallelogram whose base is 42 cm and height is 9 cm.   Hint       4. If the area of a trapezoid is 243 m2 and its parallel sides are 15 m and 12 m, find the distance (in m) between them.   Hint       5. The area of a quadrilateral is 1512 m2. The lengths of the perpendiculars from the opposite vertices to a diagonal are 14.6 m and 12.4 m respectively. What is the length (in m) of this diagonal?   Hint       6. If the lengths of the diagonals of a rhombus are 18 cm and 40 cm respectively, find its area (in cm2).   Hint       7. The diagonals of a quadrilateral intersect at right angles. The lengths of the diagonals are 16 cm and 13 cm respectively. Calculate the area (in cm2) of the quadrilateral.   Hint