In a salt marsh ecosystem, marine biologists analyzed the energy flow between trophic levels. They estimated that the energy incorporated into the primary consumers' (herbivores) trophic level was 360 000 J m−2 yr−1360\,000\text{ J m}^{-2}\text{ yr}^{-1}360000 J m−2 yr−1. The energy within the primary producers' trophic level was 450%450\%450% greater than that of the primary consumers.
Calculate the energy in the primary producers' trophic level in kJ m−2 yr−1\text{kJ m}^{-2}\text{ yr}^{-1}kJ m−2 yr−1.
Calculate the percentage efficiency of the energy transfer from primary producers to primary consumers. Give your answer to two significant figures.