Identify the correct statements from the following 

a) Dichloromethane is used as a solvent

b) Freons are used for refrigeration
c) ${\mathrm{CCl}}_4$ causes depletion of ozone layer

d) Electrophilic substitution reactions halo benzenes occur faster than those of benzene

• Dichloromethane may dissolve a variety of organic compounds, despite the fact that it is not miscible with water. These characteristics make DCM a very powerful solvent in many industrial processes, especially when paired with its volatility.
• The colourless gas is dichlorodifluoromethane (R-12), a chlorofluorocarbon halomethane (CFC) used as a refrigerant, is typically supplied under the brand name Freon-12.

Approximately 10% of the chlorine in the troposphere is found in carbon tetrachloride, a chemical that depletes ozone.