1.How did the ancient Egyptians do that? 4,000 years ago there was no machinery. How could they move such enormous blocks to build such a huge pyramid?

2.We`ll invent new kinds of machinery to mine underground for us and nobody can tell exactly how much coal there is underground. Atomic energy can`t take the place of coal because it`s too dangerous to produce. Once leakage occurs, it`ll bring disastrous r