what the standard your client must show to get a variance to allow him to build the gas station

Your client, Jim, lives in Worcester, Massachusetts. He owns a downtown Worcester property that is zoned for commercial office space. However, since there is already plenty of office space available in Worcester, Jim does not feel that it would be wise to build another office building. Instead, he wishes to build a gas station to service the downtown traffic.

He asks you to do a bit of research on Massachusetts law to determine:

a) what the standard your client must show to get a variance to allow him to build the gas station; and

b) if you can find any case law on the basis of which to guess whether he will be successful.