One of darwin's principles is that minor variations in all traits exist within species. why is this idea important to his theory of evolution?

Which statements are true of a scientific theory but not a hypothesis

The observations of hooke and van leeuwenhoek documenting the existence of microscopic cells formed the basis of what important theory? a. the cell theory stating that all living things are composed of cellsb. the theory of spontaneous generation, which held that life forms could arise spontaneouslyc. the theory of chemotherapy, or use of antimicrobials to destroy pathogenic organismsd. the germ theory of disease and causative agents

Which units ate used to measure both velocity and speed? check all that apply