i think its mississippi river
A volcano with an empty magma chamber would be called a caldera
Explanation: During certain types of explosive eruptions, a volcano's magma chamber may empty enough for an area above it to subside, forming a type of larger depression known as a caldera.
C, the separation of Church and State
State Route 88 (SR 88), also known as the Carson Pass Highway, is a California State Highway that travels in an east–west direction, from Stockton, crossing the Sierra Nevada at Carson Pass, and ending at the border with Nevada, whereupon it becomes Nevada State Route 88, eventually terminating at U.S. Route 395.