Answer: Microscope
Explanation: This is a kid answering :)
Answer:
CaCl2
Explanation:
For every calcium there's 2 chlorine
C I think is the right answer
Answer: (4) 
Explanation:-
According to Arrhenius concept, a base is defined as a substance which donates hydroxide ions
when dissolved in water and an acid is defined as a substance which donates hydronium ions
in water.
1.
is a strong electrolyte and thus dissociate in water.
2.
is a non electrolyte and thus do no dissociate in water.

3.
is a strong electrolyte and thus dissociate in water.

4.
is a weak electrolyte and thus partially dissociate in water.

The release of O₂( oxygen) from the process of photosynthesis is what made them to be able to float.
<h3>What is Photosynthesis?</h3>
This is referred to as the process in which green plants manufacture their food in the presence of sunlight which is trapped by chlorophyll.They are known as primary producers and they use compounds such as water and carbondioxide.
The reactants mentioned above undergo series of reactions which leads to the production of glucose and oxygen is given off as a result which is the element responsible for the floating of the aspirated spinach leaf disks in this scenario.
Read moire about Photosynthesis here brainly.com/question/19160081
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