Which expression can be used to find the surface area of the following rectangular prism

Jeffery conducted a survey in his school and found that 30 of the 50 eighth grade students' favorite subject is mathematics. based on the results, jeffery concluded that out of the 200 students in his school, 120 students' favorite subject is mathematics. select the statement that is true about jeffery's conclusion. a. jeffery's conclusion is not valid because the sample was biased since only 200 students were surveyed. b. jeffery's conclusion is valid because the sample was random since all of the students were eighth grade students. c. jeffery's conclusion is valid because the sample was random. d. jeffery's conclusion is not valid because the sample was biased since all of the students were eighth grade students.

Use set builder notation to represent the following set: { -3, -2, -1, 0}

Phyllis and chen are saving money to go to a football game. each friend starts with some money and saves a specific amount each week. phyllis made a graph to show the total she has saved at the end of each week. chen wrote an equation to show the total, y, he has saved at the end of each week, x. y = 15x + 15 compare the amount that each friend has when both friends start saving. select the correct answer from the drop-down menu to complete the statement. phyllis starts with $ and chen starts with $