Answer: I believe the answer is A.
Explanation: Well, the lithosphere is rocks and earth, the hydrosphere makes up all the water on Earth, the biosphere is us, (living things,) and the atmosphere is the air that surrounds us and our planet. So if you go in order, it's basically lithosphere, hydrosphere, biosphere, and then atmosphere.
Answer:
Check if the ions of two compounds exchange places.
Explanation:
The definition of single replacement is a reaction when an ion replaces another ion, thus the name.
Answer: yes
Explanation: its common sense
Independent variable: the student chooses to miss class.
dependent variable: in result of the student missing class his grade goes down.
hyposthesis: if the student misses class multiple times, then his grades will go down.
