I. (1, 30)1. What are the essential differences _ selling and marketing?A) between B) from C) among D) for2. Jack called the airline to _his flight to Beijing this morning.A) improve B) believe C) confirm D) insure3. It was in the year of 2002_they set up a branch company in China.A) as B) that C) what D) which4. Youd better _ad