1. (2020六下·洛阳月考) 请按要求完成下列各题。

1. （1） When my dad celebrated his 31st birthday, I was 8 years old. Now, my dad is twice (两倍）the age I am. What's my age now?
3. （2） A bottle of juice sells at the price of 1 yuan. The juice is worth 0. 9 yuan more than the bottle itself. How much does an empty bottle cost?
5. （3） Can you add operations to the formula to make it correct?

   8__4__2__9=25

7. （4） Mr. and Mrs. Bing have 7 daughters, each of their daughters has a brother. How many children do Mr. and Mrs. Bing have?
9. （5） What's the next number? 
   4、6、10、18、34、