Design a plan to collect data on one of the following possibilities: 1. There is a correlation between limpet abundance and degree of exposure. 2. There is a correlation between the shape of the limpet's shell and degree of predation. 3. There is a correlation between limpet size and its vertical position on the shore. Choose one relationship and list the measurements that need to be made. Identify the independent and dependent variables as well as any confounding variables.