Why is the theory of plate tectonics considered a theory and not a hypothesis

20 in the formula no3, what does the subscript 3 mean?

(drag each tile to the correct identify which questions can be answered by what can be answered by science or which cannot. -is it right or wrong to use genetic engineering to produce new food products? -what are the most common social settings that tend to produce accomplished artists? -if a new gene is added to the genome of a tomato species, will that species be more resistant to insects? -should humans use biotechnology to bring extinct organisms from the fossil record back to life? -do the types of organisms found in the fossil record appear in consistent sequences in different parts of the world? -are michelangelo's paintings more impressive than rembrandt's?

Coral reefs support more species per unit area than any other marine environment on earth. what is one way coral reefs are important to the health of the biosphere