An observation study is where nothing changes and you record what is seen. An experimental study you have a control group and a testable group.
The answer would be: .C. The groups in an experiment are chosen at random, but not in an observational study.
-3+7=4 should be your answer
Answer:
Step-by-step explanation:
Answer: no solutions
Step-by-step explanation:
12x+32=12x-7
12x-12x=-7-32
0x=-39
No solutions
Answer:
0
Step-by-step explanation: