The answer is 50 kcal by the formula of 10% - 500kcal x .1 = 50 kcal it is the approximately chemical energy that can contain by the secondary consumers.
1%- 500,000 kcal x .01 = 5,000 kcal for producers.
10%- 5,000 kcal x .1 = 500 kcal for primary consumers.
10%- 500 kcal x .1 = 50 kcal for secondary consumers.
10%- 50 kcal x .1 = 5 kcal for tertiary consumers.
Each trophic level receives less and less energy, so fewer organisms can be supported at higher levels.
10% of energy gets passed to next level in form of chemical bonds and 1 decimal place.
