Which of the following describes the frequency, graphed as a valued of a population, which results as a bell-shaped curve?

a. circular distribution
b. normal distribution
c. abnormal distribution
d. hectal distribution

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