Which statements explain what the fossil record indicates? check all that apply. earth is 4.5 billion years old. many organisms have become extinct. mammals have always existed on earth. mass extinctions have occurred several times on earth. the amount of water on earth has decreased over time.
its 2 and 4

- Many organisms have become extinct

- Mass extinctions have occurred several times on Earth

Explanation:

The fossil records show us lot of things about the Earth. They show us approximately when the life occurred on our planet, as well as the type of living organisms that lived in the past. They are a witness of the evolution of the organisms, and show us that lot of species lived in the past and over time either evolved into other species or died out. One big clue that the fossil records offer are the mass extinctions, as there are sharp changes in the living organisms at certain points of the geological past, where most of the organisms don't appear in the fossil records anymore.

Earth is 4.5 billion years old

Many organisms have become extinct

Mass extinctions occurred several times on Earth

The amount of water on Earth has decreased over time

Explanation:

The time chart seen in the lesson states that earth was formed 4.5 billion years ago

The lesson states many organisms have become extinct but that is also common knowledge (mammoths, dodos, dinosaurs, etc)

The time chart shows that living things were introduced much later after earth was formed. (First single celled life appeared 4.1 billion years ago, .4 billion years AFTER earth was formed.)

The lesson states mass extinctions occurred several times but this is also common sense.

The amount of water has decreased on Earth. I'm not sure if this is explicitly stated in the lesson videos but if you think about it, water is being used up by humans every day, and Earth has utilized its water for many things over its 4 billion years of existence. We have obviously lost water.

answer; ///i believe that the correct answer is (a) specialized cells)

b tumor cells have a cell wall instead of a membrane

explanation:

tumor cells different from normal cells because tumor cells have a cell wall instead of a membrane.