What is the hazy layer that surrounds a comet's nucleus?

What happens when a magniseum ion ia atracked to a chlrene ion

What do scientists need to look at before developing an argument

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