You want to do a survey on how religious people are in your town. what do you need to have a valid scientific sample? check all that apply.

I believe the answer is:

random sample of the town's population

A mix of participants that reflect your town's makeup

Random sample is needed in order to ensure that the researchers do not obtain only the subjects that is close to them. Mix of participants is needed in order to ensure that the sample population are not taken from group with close similarties in behaviour.

even though you have attached neither the chart nor the generalizations, i have located them online. the right answer is d, since they are asking you about a generalization. you can only infer from the chart that between 2008 and 2009 the number of employed workers decreased significantly (from over 115 millions to 107 millions approximately), which signals some type of economic crisis.