Solution is in the attachment.
(-3, 5, 6)
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

=> 
=> 
False. it said ,"The sum of the exterior angles of a polygon is always 360 degrees<span>. ... By an inductive proof, this is </span>true<span> for all </span>polygons." that is what i think.