Choose the correct words in the conditional sentences. 1.if scientists find/found a cure for aids, it would save lives around the world. 2.if diseases didn't/don't exist, more people would reach their 100th birthday. 3.if we use up all the world's oil, we need/ll need more renewable energy. 4.if oil prices continue to rise, petrol gets/will get more expensive too. 5.if scientists made human clones, i think the world will/would be a dangerous place