46. The board of the company has decided to ______ its operations to include all aspects of the clothing business.

A) multiply B) lengthen C) expand D) stretch

47. His business was very successful, but it was at the ______ of his family life.

A) consumption B) credit C) exhaustion D) expense

48. First published in 1927, the charts remain an ______ source for researchers.

A) identical B) indispensable C) intelligent D) inevitable

49. Joe is not good at sports, but when it ______mathematics, he is the best in the class.

A) comes to B) comes up to C) comes on to D) comes around to

50. Doctors warned against chewing tobacco as a ______ for smoking.

A) relief B) revival C) substitute D) succession

46.C) expand 47. D) expense 48.B) indispensable 49.A) comes to 50.C) substitute