Hi there!
I believe the answer to this is B. Elementary and High school students.
Hope this helps! ☺♥
The correct scientific instrument is telescope.
Answer:
b) +2 and +3.
Explanation:
Hello,
In this case, given the molecular formulas:

And:

We can relate the subscripts with the oxidation states by knowing that they are crossed when the compound is formed, for that reason, we notice that oxygen oxidation state should be -2 for both cases and the oxidation state of X in the first formula must be +2 since both X and O has one as their subscript as they were simplified:

Moreover, for the second case the oxidation state of X should be +3 in order to obtain 3 as the subscript of oxygen:

Thus, answer is b)+2 and +3
Best regards.
Answer: Observation is essential in science. Scientists use observation to collect and record data, which enables them to construct and then test theories
Explanation:
42.4 ml is the volume in milliliters of the lead ball if a lead ball is added to a graduated cylinder containing 50.6 ml of water.
<h3>What is a graduated cylinder?</h3>
A tall narrow container with a volume scale is used especially for measuring liquids.
The graduated cylinder contains water
mL is a volume unit.
Water volume = 50.6 ml
The lead ball caused an increase in volume from 50.6 ml to 93.0 mL.
The new volume is the lead ball volume plus the original water volume :
Final volume = Vlead ball+ Water original volume



Hence, 42.4 ml is the volume in milliliters of the lead ball.
Learn more about the graduated cylinder here:
brainly.com/question/13386106
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