You would expect 25 Kcal of energy stored in trophic level 4.
<u>Explanation:</u>
Energy flow in the ecosystem follows 10% law according to which 10% of the energy in the lower trophic level is transferred to the next trophic level.
In this example grass belongs to the first trophic level, producers.
Energy of grass=25000Kcal
Energy transferred to trophic level 2=10% of 25000=2500
10% of the energy in trophic level 2 is transferred to trophic level 3.
Hence energy at trophic level 3=10% of 2500=250Kcal
Energy transferred to trophic level 4=10% of energy in trophic level 3
=10% of 250=25Kcal
Energy to be stored in trophic level 4=25Kcal