PLEASE HELP which half of the celestial sphere is visible to a northern hemisphere observer?
a. latitudes greater than 0
b. latitudes less than 0
c. latitudes between 0 hours and 6 hours
d. latitudes greater than 20 N

The eruption of a nearby volcano causes a prairie ecosystem to receive a lot less sunlight. which of these is most likely effect on the ecosystem?

Which structure in the cardiovascular system connect arteries to veins?

If you were given a map of the sensory cortex in the postcentral gyrus of the cerebrum, do you think the map would have more “space” devoted to the regions of the body that have the highest density of sensory receptors, or the regions of the body that have the lowest density of sensory receptors? explain.