18. When dilute hydrochlonc acid (HCI) is placed on the sedimentary rock limestone and the nonsedimentary rock marble, a bubbling reaction occurs with both. What would this indicate? 1. The minerals of these two rocks have similar chemical compositions. 2. The molecular structures of these two rocks have been changed by heat and pressure. 3. The physical properties of these two rocks are identical. 4. The two rocks originated at the same location.​