Here are the answers to question 7 based on the provided passage:
7. Read the following passage carefully and answer the questions on it.
a) How long can the tropical rain forest survive? If the rainforest is a stable self-maintaining ecosystem which has survived the hazards of millions of years, why is it now decreasing in area so rapidly that its survival is being threatened?
Step 1: Determine how long the rainforest can survive.
The passage states, "Clearly, the answer is that it cannot survive the attacks of modern man who is equipped with the resources of advanced technology."
Therefore, the tropical rainforest cannot survive indefinitely under the current conditions of modern human intervention.
Step 2: Explain why its survival is now threatened despite its long history.
The rainforest has survived natural hazards for millions of years because it is a "stable self-maintaining ecosystem" with "natural selection has provided the forest ecosystem with mechanisms for withstanding such natural hazards