What do you need help with
C)Neuron... hope it helps :)
Answer:
Questionnaires
Explanation:
They allow both government and outside researchers to obtain estimates of a variety of health related topic or issue among either the entire nation or specific demographic group of the population.
And the survey design is cross section.
If you take a kids class then yes, depending how old you are, how fast you learn, and if it is meant for you.