Last option that is none of above is right answer.
<span>Electron microscopes can magnify objects to 10,000,000x the smallest object that can be viewed is larger than an electron. Electron microscopes can improve the resolution that is achieved by light microscopes. Entire cells can be viewed and their components.</span>
Using accurate measurements, using pure chemicals and performing the reaction under the most ideal conditions is important to get a valuable percent yield.
<h3>How we calculate the percent yield?</h3>
Percent yield of any chemical reaction is define as the ratios of the actual yield to the theoretical yield of the product and multiply by the 100.
To get the high percent yield or actual yield of any reaction, we have to perform the reaction under ideal condition because if we not use the standard condition then we get the low rate of reaction. Reactants should be present in the pure form as impurity make unwanted products and reduce the productivity of main product and accurate amount of reactants also important for the spontaneous reaction.
Hence, options (a), (b) & (c) are correct.
To know more about percent yield, visit the below link:
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200 is the answer let me know if you need anything