How many times does the minute hand on the clock face rotate exactly from 7:30 to 8:00?
钟面上的分针从7时30分开始8时正好旋转了多少周．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<result>1/2 = around 0.5</result>