Question: What is the size of babies as they develop whilst in the womb?

Question: I remember being told at university that if you squeezed the end of a hose pipe & restricted the flow, the jet of water would cover a larger distance. As the flow rate is constant, the speed increases to compensate. I think this is to do with the conservation of momentum. However, when a fluid is travelling supersonically the opposite is true! This is why rocket engine exhausts actually diffuse the jet to create the same effect. This to me is against common sense. Would you happen to know in lay mans terms why this is the case? I hope someone can help.

Question: By how much are continents thought to move each year?

Question: Four leaf clovers occur because of a genetic mutation in the common, 3-leaf clover plant. I'd be interested to know what is the probability of finding a 4-leaf clover? And have people been able to isolate this mutation and create plants that solely produce 4-leaf clovers?