Answer to Question 1
Continental islands are islands situated on continental shelves or are fragments that have been broken off of a continent.
Most high islands are the result of volcanic eruptions.
The low islands are made of coral, a material composed of the skeletons and living bodies of small marine organisms that inhabit tropical seas.
Answer to Question 2
People have intentionally or accidentally introduced to the island alien plant and animal species, known as exotic species and including rats, snakes, sheep, pigs, cattle, and fast-growing plants, that often end up preying on or overtaking the endemic species. Habitat destruction and deliberate hunting also lead to extinction.
Australia's Great Barrier Reef (the world's largest coral reef system) is facing threats from warming ocean waters, overfishing, and pollution runoff. The Hawaiian Islands have become known to ecologists as the extinction capital of the world because of the irreversible impacts that exotic species, population growth, and development have had on indigenous wildlife there. Environmentalists are also concerned about the impact of commercial logging on the island of New Guinea.
Because they have developed in the absence of natural predators and inhabit relatively small areas, island species are especially vulnerable to the activities of humankind.
Answer to Question 3
nuclear