Asolution that is a 4 on the ph scale is a
a. weak acid
b. strong acid
c. weak base
d. strong base

stimulus is a change in the environment that causes an organism to react. the response is the reaction to the stimulus. some examples of stimuli for zebras are drought, to many predators, and bad feeding grounds such as dead grass or plants. zebras respond to stimuli just like all other living organisms

c. heat from the poles back down towards the equator.

layer 3 is younger than layer 6.