I think it might be a or b but I’m 97% sure the answers is b
It take 0.54 hours to deposit 6.36g of copper
<h3>Further explanation</h3>
Faraday's Law I
"The mass of the substance formed at each electrode is proportional to the electric current flowing in the electrolysis
W = e.i.t / 96500

e = equivalent = Ar / valence
i = current, A
t = time, s
W=6.36 g
e = 63.5 : 2 =31.75
i = 10 A

In the crystallization process the solid compound is dissolved in the solvent at elevated temperature and the crystallize product obtained by slow cooling of the solution. Here the solubility of acetanilide at 100°C is 1g per 20mL of water. Thus to dissolve 500mg of acetanilide at high temperature that is 100°C we need 10mL of water.
Now at 25°C after the re-crystallization there will be some amount of dissolve acetanilide. Which can be calculated as- 185mL of water is needed to dissolve 1g or 1000mg of acetanilide at 25°C. Thus in 10mL of water there will be
gmg of acetanilide.
Chemical change happens when a substance combines with
another substance to form a new substance. It produces chemical reactions and
generally is not reversible except by further chemical reactions. Heat is sometimes
produced in some reactions. When chemical reactions occur, the atoms are
rearranged and an energy change happens along with it as new products are
generations. At a molecular level, chemical changes involves the making or
breaking of bonds between atoms. Some examples of chemical change are iron
rusting (iron oxide forms) and bread rising (yeast converts carbohydrates into
carbon dioxide gas).