Astudy was conducted on 100 randomly selected chefs in the united states. the study consisted of a survey that the chefs had to fill out and send in. all surveys were returned, but on one of the questions on the survey concerning salary only 70 chefs answered. identify the problem with this study.
a. the conclusion is based on a bad sample.
b. a nonresponse occurred.
c. this is a self-interest study.
d. the relationship between two variables implies one causes the other.

Getting rid of my account might as well do it with some fun an old man was sitting on a bench at the mall. a young man walked up and sat down next to him. he had spiked hair in different colors: green, red, orange, blue and yellow. the old man just stared at him. the young man turned to him and said sarcastically, "what's the matter, old timer, never done anything wild in your life? " without batting an eye, the old man replied, "got drunk once and had sex with a parrot. i was just wondering if you were my son."

The critical period for development, when exposure to disease prenatally can have the most devastating effects of growth, is

B. speculate about one positive way and one negative way that this boundary has affected the geographical units it separates over time.