Which expression is equivalent screenshots attached, !

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.

Jamie went to home depot.she bought 25 bags of soil that cost $9 per bag.she bought 15 pots at $8 each, and she bought 23 bags of pebbles at $15 each.she used a coupon that gave her $5 off for every 100 dollars she spent. how much did jamie pay at the end?

Plz ( true - false) all triangles have interior angles whose measure sum to 90.