A ship departs from city A at 7:00 am and arrives at city B at 4:00 pm. The ship travels an average of 28 kilometers per hour. How many kilometers is the sea voyage from city A to city B?
一艘轮船于上午7：00从A城出发，下午4：00到达B城，轮船平均每小时行驶28千米．从A城到B城的海上航程是多少千米？
<gadget id="calculator">16 - 7</gadget>
<output>9</output>

<gadget id="calculator">28 * 9</gadget>
<output>252</output>

<result>252</result>