If a= {1,2,3} and b= {1,2,3,4,5,6,7,8} then a u b

a. {1,2,3}
b. 0
c. {1,2,3,4,5,6,7,8}

Running and sleep. sufficient sleep is important for adolescents for both their neural and psychological development. despite this, daytıme sleepiness and poor physical and psychological functioning related to chronic sleep disturbances are common. there is a growing body of evidence that exercise is associated with both better sleep and improved psychological functioning sixty participants were recruited from a high school in northwesten switzerlandthey were randomly assigned to either a running group or a control group, 30 to each group the running group ran every moming for a little over 30 minutes on weekdays for a three-week period. all participants used a sleep log for subjective evaluation of sleep, and sleep was also objectively assessed at the beginning and end of the study using a sleep electroencephalographic device that measured quantities such as sleep efficiency and time spent in the four different sleep phases. running was found to have a positive impact on both objective and subjective measures of sleep functioning what are the explanatory variable(s) and the response variable(s)? (a) outline the design of the experiment (b) (c) here are some more details on the treatment and control groups. all participants arrived at school at 7 a. m., and the running group did two laps on the track and then ran cross countrv in groups of at least four people for 30 minutes the control group remained seated at the track, worked on horpework. and interacted with each other. when the runners returned, all participants prepared for school and ate a breaktast that was provided. iwhy do you think the experimenters had the control group arrive at 7 am interact withdassmates and have breaktast together? explain. do you think having the control eroup do these activities is important for the types of conclusion that can be reached? how?

Asociologist wants to study a culture that occurs in some women’s prisons: “state families,” in which individual prisoners take on certain roles within a group of like-minded prisoners. there is previous evidence that younger prisoners will use older inmates who play the roles of grandparents as a resource before they will turn to staff for and advice. the lieutenant in charge of a dorm of long-term prisoners offers to gather volunteers to speak to the researcher and also offers to vouch for the integrity of the researcher. the use of this staff is: a valid use of a statistical technique referred to “snowball sampling” wherein the inclusion of the first subject leads to the recruitment of another one subject. a useful tactic in obtaining a sample of prisoners who both meet the criteria and who will be honest with the researcher. wrong and is prohibited; subject selection needs to be free from intervention by prison authorities or prisoners. acceptable only when the researcher’s irb grants a special waiver.

Which beliefs and principles in the declaration of independence and the us constitution create a national identity