A certain investment has had returns of 10%,20%, and 30% over the past three years. What is the geometric mean return over that period? 2. The ages of a group of five friends are 20,25,30,35, and 40 . What is the geometric mean of their ages? 3. The heights of a group of plants are 5 cm,10 cm, and 15 cm. What is the geometric mean height of the plants? 4. The lengths of the sides of a right triangle are 3 cm and 4 cm. What is the length of the third side (the hypotenuse), in terms of the geometric mean of the other two sides? 5. Suppose you have a dataset of test scores for a class of 20 students. The scores are as follows: 80,85,90,92,95,85,78,89,92,86,83,88,91,80,92,85,88,84,87,89. What is the mean test score for the class?