'Lang factor' is defined as the ratio of the capital investment to the delivered cost of major equipments. The value of 'Lang factor' for fixed capital investment, for a solid-fluid processing chemical plant ranges from

A. 1.2 to 1.4

B. 2.5 to 2.7

C. 4.2 to 4.4

D. 6.2 to 6.4

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