Answer:
70 kCal
Step-by-step explanation:
With every increase in the level of the food chain/pyramid, only 10% of the calories are passed on. (The rest are lost as heat)
So, form producers to primary consumers we have:
7,000 kCal x 0.10 = 700 kCal
**I multiplied by 0.10 to show that only 10% of the kCal move on
Then, from primary consumers to secondary consumers:
700 kCal x 0.10 = 70 kCal (the answer)