Choose the best answer from the four choices marked A,B,C, and D.1 The mystery customer's task is to____.A. find out the quality of businesses' serviceB. check the shop's facilities (设施)C. buy the things they needD. help other customers buy what they want2 The sentence "It's a challenging job, but a rewarding one." means that____.A. it's not a good job, so you should not take itB. the job will bring you a lot of moneyC. it's a difficult job, and the pay is lowD. the job is difficult, but it is worth doing