The surface of wa

a) Phytoplankton- Algae are tiny free floating organisms on surface of water.

b) Food chain= Algae- tadpole- water beetle- fishes.

c) Aquatic food chain is the name given to the above food chain because this food chain exists in aquatic bodies where algae are producers, tadpoles are primary consumers, water beetles are secondary consumers and fishes are tertiary consumers.

d) i) Water beetles- secondary consumer

ii) Algae-producers

iii) Fishes- tertiary consumer

iv) Tadpole- primary consumer

e) If the tertiary consumer gets 0.2J of energy from the secondary consumer, then the producer would have received 20000J of energy from the sun. This is because of the 10% energy law. Producer receives 20,000J energy from sun and uses 1% of it to make food. 200J of energy is available at the producer. 10% of 200J is transferred to primary consumer which is 20J. Secondary consumer will obtain 10% of 20J=2J. The tertiary consumer will at last receive 10% of 2J which is equal to 0.2J. Thus, 20,000J energy was radiated from sun to producer.