There are two piers A and B on a river, A is upstream and B is downstream. A and B set off from A and B at the same time respectively, row towards each other, and meet each other 4 hours later. If A and B set off from A and B at the same time respectively, rowing in the same direction, B will catch up with A after 16 hours. It is known that A's speed in still water is 6 kilometers per hour, how many kilometers per hour is B's rowing speed in still water?
一条河上有A，B两个码头，A在上游，B在下游．甲、乙两人分别从A，B同时出发，划船相向而行，4小时后相遇．如果甲、乙两人分别从A，B同时出发，划船同向而行，乙16小时后追上甲．已知甲在静水中划船的速度为每小时6千米，则乙在静水中划船每小时行驶多少千米．
<gadget id="calculator">6 * 4</gadget>
<output>24</output>

<gadget id="calculator">6 * 16</gadget>
<output>96</output>

<gadget id="calculator">24 + 96</gadget>
<output>120</output>

<gadget id="calculator">16 - 4</gadget>
<output>12</output>

<gadget id="calculator">120 / 12</gadget>
<output>10</output>

<result>10</result>