Suggest how we know when the different kinds of organisms first appeared on earth

microscopic organisms

Explanation:

The earliest life forms we know of were microscopic organisms (microbes) that left signals of their presence in rocks about 3.7 billion years old. ..Evidence of microbes was also preserved in the hard structures (“stromatolites”) they made, which date to 3.5 billion years ago

The earliest life forms we know of were microscopic organisms (microbes) that left signals of their presence in rocks about 3.7 billion years old. Evidence of microbes was also preserved in the hard structures (“stromatolites”) they made, which date to 3.5 billion years ago.

Explanation:

the index of refraction of the second medium is higher. i just took the test trust me !

a

explanation: