I need help w/ both so plz help

1. the is the thinnest part of the earth. 2. the is the thickest part of the earth. 3. what metals are mentioned in the text?

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

This is the diveristy of ecosystems natural communites and habits it is the variety of ways that species interact with each other and their environment