There are 2 roads from home to school, and 2 roads from school to store. How many roads are there from school to store?
从家到学校有2条路可以走，从学校到商店有2条路可以走，从家经学校到商店共有多少条路．
<gadget id="calculator">2 * 2</gadget>
<output>4</output>

<result>4</result>