At 9:30, what is the angle between the hour hand and the minute hand?
9：30时，时针与分针的夹角是多少．
<gadget id="calculator">30 / 60</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">3 + (1/2)</gadget>
<output>7/2 = around 3.5</output>

<gadget id="calculator">30 * (7/2)</gadget>
<output>105</output>

<result>105</result>