The diagram shows some organisms in an Antarctic food chain.
Sun-Algae
→ Krill
Cod
Seal -
Whale
Which BEST describes the role of krill in this food chain?
producers
decomposers
primary consumers
secondary consumers

Scientists often deal with numbers that are either very large or very small. for example, the radius of the sun is approximately 696,000 kilometers, while bacterial cells are as small as 1.9 × 10-4 millimeters. express each of these numbers in an alternate form.