Which 3 ideas are true?

A. Invertebrates are more efficient at using their energy than vertebrates are.
B. 90% of the energy of the primary consumer level is lost from the ecosystem as heat.
C. Energy goes from producers to consumers to detritivores and then back to producers.
D. Most of a biomagnified substance like DDT will end up in the primary consumer level.
E. 5% of the energy from the producer level goes to the primary consumer level.
F. 1% of the energy of the producer level is available to the secondary consumer level.