Who developed classification system for living things?

What type of electromagnetic wave are microwaves and radar

Which of the following statements is true? 1. the mantle of the earth is made of solid nickel and iron. 2. the crust of the earth is made of solid nickel and iron. 3. the inner core is made of solid nickel and iron.

Which kind of worm has a closed circulatory system? a planarian b fluke c pinworm d an earthworm