1)How old is our planet?
2)In which age the plants began to appear?
3)Who arrived to the Earth eight month ago?
4)Who began to communicate last week?
5)When the Ice Age covered the Earth?
6)How many hours modern man lived on this planet?
7)What began to do the man during last hour?
8)How many seconds ago the large and industrial cities began?
9)What did the modern man during those sixty seconds of biological time?
10)By whom were killed humdreds of speciesof animals?