Answer:
hi
Step-by-step explanation:hi
Answer:
The value is 
Step-by-step explanation:
Generally the productivity rate is mathematically represented as

Here K is the ha the farmer could harvest in an hour and Z is a typical yield of corn in kg/ha
Now considering 1970
The productivity rate is

=>
Now considering 1940
The productivity rate is given as
Generally the productivity ratio is mathematically ration is mathematically represented as

=> 
=> 
Answer:
D
Step-by-step explanation:
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