All musical sounds have a wave pattern that can be represented as O a series of half step notes. o the sum of one or more individual constant frequency waves O a very simple constant frequency wave. 4 pts D Question 8 An experiment is single-blind if o the participants do not know whether they belong to the treatment or the control group. o it lacks treatment group. itlades a control group Question 9 4 pts Consider an experiment designed to test whether cash incentives improve school attendance. The researcher chooses two groups of 100 high school students. She offers one group $10 for every week of perfect attendance. She tells the other group that they are part of an experiment but does not give them any incentive. This describes o an experiment that is not blinded at all. o a single-blind experiment. O a double-blind experiment