Giả sử cần tính trung bình cộng giá trị của các ô C4 và D4. Công thức nào sau đây là đúng?

=(C4+D4)*2

=2/(C4+D4)

 =(C4+D4)/2

=(C4+D4):2

There are many reasons (1) ____ it is important to have a hobby. First of all, a hobby can be a remedy for your (2) ____. Because it is the activity you choose for yourself, it will always give you pleasure and (3) ____ you relax. Even if you just spend a little time enjoying your hobby, you can see the difference (4) ____ your spirit. Second, some hobbies can also (5) ____ you financially. Many old people enjoy gardening. They grow a lot of trees and vegertable, so they can sell them for some money. In (6) ____, a hobby can help you connect with other people. If you like colecting stamps, you can (7) ____ a stamp club to share your albums with other collectors. If your hobby is caving eggshells, you can give your products to your friends (8) ____ gifts."
1.    A.for               B. why           C.because
2.    A.happiness     B.pain            C.tiredness
3.    A.help             B. have           C. do
4.    A. for              B. in               C. on
5.    A.harm           B.give             C.benefit
6.   A. addition       B. general       C.conclusion
7.   A.take part       B.go               C. join
8.    A. like            B.as                C.for