S1:tForecasting the weather has always been a difficult business.P :tDuring a period of drought, streams and rivers dried up, the cattle died from thirst and were ruined.Q :tMany different things affect the weather and we have to study them carefully to make accurate forecast.R :tAncient Egyptians had no need of weather in the Nile Valley hardly ever changes.S :tIn early times, when there were no instruments, such as thermometer or the barometer, man looked for tell-tale signs in the sky.S6:tHe made his forecasts by watching flights of the birds or the way smoke rose from fire.The Proper sequence should be:

S1:tForecasting the weather has always been a difficult business.P :tD

1.	S1:tForecasting the weather has always been a difficult business.P :tDuring a period of drought, streams and rivers dried up, the cattle died from thirst and were ruined.Q :tMany different things affect the weather and we have to study them carefully to make accurate forecast.R :tAncient Egyptians had no need of weather in the Nile Valley hardly ever changes.S :tIn early times, when there were no instruments, such as thermometer or the barometer, man looked for tell-tale signs in the sky.S6:tHe made his forecasts by watching flights of the birds or the way smoke rose from fire.The Proper sequence should be:
A.	PRQS
B.	QPRS
C.	QRPS
D.	SPQR
Answer» C. QRPS