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: There was a time Egypt faced economic crisis.
P: Cotton is the chief export commodity of Egypt.
Q: Foreign trades depend on cultivation of cotton on large scale.
R: It became necessary for Egypt to boost cotton crops.
S: Only by means of increasing foreign trade Egypt could survive.
S6: Egypt was able to sustain itself by its cotton produce.
The Proper sequence should be: