【B1】 【B3】

Look at your watch for just one minute. During that time the population of the world increased by eight five people. Perhaps you think that isn’t much. In the next hour, more than 5,000 additional people will be living on this planet. So it goes, hour after hour. In one day, there are about 120,000 additional mouths to feed. Multiply this by 365. What will happen in 100 years?
    This population explosion may be the greatest challenge of the present time. Within the next forty years, the world population may double. Can the new frontiers of science meet the needs of the crowded world of tomorrow?
    If the present rate of population increase continues for the next 600 or 700 years, there will be standing room only. Each person will have between 3 to 10 square feet of space in which to live. This includes the mountaintops, deserts, and the ice and snow fields of the polar regions. Of course, no one expects such a thing to happen. War, plague, famine, or some other catastrophes can be expected to occur long before the population reaches this point. Actually, the danger is not in an overcrowded world where people are huddled together so that they cannot move arms and legs, but in an upset balance between population and resources.