Yes it could be one........
Answer:
and 
Step-by-step explanation:
Given

Required
Find x and y
In the second equation. Assume that:

Substitute
in the first equation


Collect like terms


Multiply through by 5


Solve for x

Substitute this value of x in 





Answer:
Market economy
Step-by-step explanation:
Once again this is because they are changing their prices and items for sale because of the changes in market.
Answer:
because of the product
Step-by-step explanation: