题目内容：

请根据短文内容，在短文空格处填上一个恰当的词，使短文完整、通畅。

Mahalya is a student in Grade 8 at Lamberton Middle School in Pennsylvania, the United States. Every afternoon at two o’clock, she runs to a store at her school. She is not running there to buy any snacks. 1., she works as the storekeeper and helps count change for customers.

“I didn’t know that it took so much work. I didn’t do anything 2. this,” Mahalya told the Sentinel, a local newspaper.

In fact, she and 3. 11 students work as the storekeepers at Bison Bargains, the school’s first student-run store. It started on February 22, and it opens each school day during break time from 2:00 p.m. to 2:30 p.m. It mainly 4. stationery（文具）and snacks.

Through this, students see what doing 5. is like. Christian, a 14-year-old student , was really surprised by how hard it was not to 6. mistakes and do the transactions（交易）. “It’s kind of a challenge to learn all the information on the stock（供应物）lists and remember all the 7. of the products,” Christian told the newspaper.

To help them learn about business they took a class. The class taught students how to use money and some simple business rules.

The school did a survey on what products students would buy from a school store. In the future, they plan to sell things made by the students 8.. For example, students can sell their homemade pencil boxes and phone cases.