Each of the following studies examines the relationship between sugar consumption and activity level for preschool children. Identify which is correlational, which is experimental, and which is non-experimental. Study 2: A researcher obtains a sample of 100 preschool children. The children are randomly assigned to two groups. On arriving at school each morning, one group is given a high-sugar breakfast, and the other group is given a breakfast relatively low in sugar. After one week, each child's activity level is measured by direct observation on the playground. On average, the children in the high-sugar breakfast group had a higher level of activity than the children in the low-sugar group