Any advice for a new parent? I just had my baby.

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.

The sum of two numbers is 12 and their difference is 18 what are the two numbers

Drag each tile into the correct box. not all tiles will be used. find the tables with unit rates greater than the unit rate in the graph. then tenge these tables in order from least to greatest unit rate