In an experimental study of differing amounts of sleep affect concentration, the levels of concentration would be considered the:
a) operational definition
b) dependent variable
c) independent variable
d) control group

You began membership in a new health and fitness club which has access to a dietician and personal trainer. they you develop a special eight-week diet and exercise program. the data in the following table represents your weight, w, as a function of time, t, over an eight-week period. time (weeks) 0 1 2 3 4 5 6 7 8 weight (lb) 150 144 143 141 140 137 137 132 129 your weight decreases during each of the first five weeks of the program. determine the actual change in weight over the first five weeks of the program by subtracting your initial weight from your weight at the end of the first five weeks. what is the sign of your answer? what is the significance of this sign? a. 137-150 = -13 lb; a change in weight is negative because the weight decreases. b. 137-150 = 13 lb; a change in weight is positive because the weight decreases. c. 150-137 = -13 lb; a change in weight is negative because the weight increases. d. 150-137 = 13 lb; a change in weight is positive because the weight increases.

What effect do stimulants, such as cocaine, have on the nervous system? o a. stimulants change the activity of neurotransmitters. o b. stimulants mimic hormones and influence moods. o o c. stimulant|mchange how sensory information is processed. d. stimulants decrease brain activity.

Which piece or legislation requires employers to eliminate or minimize exposure to contaminate sharps