What can you do to avoid getting holes in your teeth?

The blue particles in this image are able to cross the cell membrane through simple diffusion. how will they be transported? outside the cell inside the cell o a. the substances will move directly across the membrane from outside the cell to inside the cell. b. the substances will move through channels in the membrane proteins from outside the cell to inside the cell. o c. the substances will move through channels in the membrane proteins from inside the cell to outside the cell. o d. the substances will move directly across the membrane from inside the cell to outside the cell.

Amineral crystallizes from magma deep inside earth. which characteristics can be determined given only the information above. a) luster b) streak c) crystal size d) crystal structure

The first supersonic flight was 1947. it was just above the speed of sound. which altitude would you expect captain yeager to have used for his flight? a) sea level b) 1000m c) 13,700m (within altitude used by commercial planes today) d) 85,000m (where meteor showers originate) will mark brainlist