In each question, the first and the last sentences of the passage are numbered S1 and S6 respectively. The rest of the passage is split into four parts. These four sentences are jumbled. Read the sentences and identify their correct and logical order.

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S1: Trucks, trains planes and refrigerator ships are new ways of carrying food.
P: In many countries, women carry food to market on their heads.
Q: High in the Andes Mountains long lines of Illamas, each with a heavy bag of grain, pick their way along rocky trails.
R: But a great deal of food is still carried on the heads of women and the backs of animals.
S: Over the desert sands, camels carry loads of salt, dates and cheese from one oasis to another.
S6: And in a lonely bay, a fisherman still rows home with the day's catch.
The Proper sequence should be: