Coca - cola was invented in 1886 by John Pemberton, a 50 years old chemist from Atlanta, USA. He decided to develop a soft drink to sell as a '' brain tonic'' . Working tiredlessly in the back room of his drugstore, he produced a (1)....................containing, among other things, coca leaves, coca nut oil, sugar and caffeine.( the exact (2)......... is still secret, but the tiny cocaine content was removed in 1903). A few months later, an assistant(3).........a customer Coca- colss mixed with soda waterby (4)...........It was this small addition that (5).............out to be the vital ingredientive that made the drink a success. 1. a. composition b. mixture c. chemical d. drug 2. a.receipt b. menu c. recipe d. prescription 3. a. provided b. supplied c. served d. presented 4. a. error b. mistake c. wrong d. misunderstanding 5. a. put b. picked c. turned d. set ( chọn đáp án đúng)