Final answer:
Without specific data on global energy needs, we cannot determine the number of 9-megaton fusion bombs needed for a year's supply of energy.
Step-by-step explanation:
To determine the number of 9-megaton fusion bombs needed for a year's supply of energy, we need to consider the total energy consumption of the world.
Unfortunately, the question does not provide any data from Table 7.1 or any relevant information. Without specific data on global energy needs, we cannot provide an accurate answer to the question.