Answer to Question 1
Answer: A marine terrace is a flattish area near the coastline. It is an erosional platform cut by waves. But, sea level has gone done relatively to the elevation of the platforms. Thus, the terraces are indicative of a tectonically active, emergent shoreline.
Answer to Question 2
Answer: There is a large amount of coral bleaching because corals are stressed for reasons not well understood. Pollution and sedimentation caused by humans might be contributory, but it is clear warming water and its increased acidification from greenhouse gases might be the prime factors.
