I believe true because the Precambrian is the first geologic time, going back 4600-570 years ago, meaning it should contain the earliest of things.
A. the mitochondria and chloroplasts are much different in structure than bacteria
The DNA is splitting in two, thymine pairs with adenine, and guanine pairs with cytosine
Cells create tissues which create organs which make up systems so i believe the answer is D i hope this helps :)
The metric system is an alternative system of measurement used in most countries, as well as in the United States. The metric system is based on joining one of a series of prefixes, including kilo-, hecto-, deka-, deci-, centi-, and milli-, with a base unit of measurement, such as meter, liter, or gram. (got the answer from google hehe)
