Question

If the amount of energy available at fourth trophic level is 5 kilo joule what was the energy available at producer level?

Answer 1

500 kilojoule would be the energy available at the producer level

Answer 2

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If 5kj of energy is available for the 4th trophic level then the organism in the 3rd trophic level would  have stored energy of 5kj

then according to 10%law the 2nd trophic level would have had ....

5kj × 100/10% = 50kj of energy

then the amount of energy in 1st trophic level (producer level)  would be

50 * 100/10% = 500kj

the producers consume only 1% of total energy from the sun

therefore energy available from the sun=500 * 100/1= 50000kj