If the grass contains 220,000 kcal of energy, who much energy will be available to the owl?

Generally, consumers only receive 10% of the energy from what they eat. So, if the grass had 220,000 kcal of energy, then the cow would receive 10% of that -  200kcal. And then when a human eats the cow, it will only receive 10% of the cow's energy. This is because within a food chain, energy is lost as organisms use their energy to survive - like moving and producing heat (if endothermic). So consumers do not get 100% of their food's energy. Hope this helps a little.

Explanation:

chemical digestion occurs in the stomach were hcl and pepsin forms chyme, the mouth in which salivary amylase breaks down starch to form bolus, and the small intestine specifically the duodenum.