When did photosynthesis begin? a about 1.2 billion years ago
b about 3 billion years ago
Cabout 4.6 billion years ago
d about 28 million years ago

Match each term to its scientific definition. a)natural world b)scientific method c)theory 1) everything that can be observed or explained scientifically 2) a well-supported explanation of all the evidence related to a natural phenomenon 3) the procedure of scientific inquiry used to investigate natural phenomena