Answer:
B) (i) and (ii) only
Explanation:
We can say that Jack is experiencing diminishing (or decreasing) marginal production since he needs to add more inputs (bags of seed) to produce smaller increases in his production of watermelons.
With the first bag of seeds he could produce 30 watermelons, so his productivity could be calculated as 30 per bag. Now with the second bag he can only produce 50 watermelons, so his productivity lowered to 25 per bag. We can elaborate the following table:
bags of seed cost of seeds watermelon produced cost per unit
1 $100 30 $3.33
2 $200 50 $4
3 $300 60 $5
As productivity lowers, the cost per unit increases.
