Science doesn’t have all the answers. And no scientist claims that it does. Of course it depends on what the question is. If the question is what it takes to put a satellite into orbit, we can answer it with absolute certainty because it’s been done. The evidence is clear. We wouldn’t be watching satellite TV if we didn’t know how to launch a satellite. If the question is about making stainless steel, or tires, or aspirin or lightbulbs or hockey pucks, we have the answers because these things exist.