There is a rectangle ABCD, the length AD is 12 cm, the width AB is 4 cm, there is a point P on AD, which travels from A to D at a constant speed of 1 cm per second; there is a point Q on the side of BC, and the speed is 4 cm per second The speed of centimeters moves back and forth at a constant speed on the side of BC. P starts from point A and Q starts from point C at the same time, and connects to PQ at any time. During the period from P to point D (including the moment when point D is reached), How many times is line segment PQ parallel to line segment AB? How many seconds after departure each time?
有一个长方形ABCD，长AD为12厘米，宽AB为4厘米，在AD上有一点P，以每秒1厘米的速度从A向D匀速行进；在BC边上有一点Q，以每秒4厘米的速度在BC边上作匀速往返运动，P从A点，Q从C点同时出发，随时连接PQ，从P出发直至到达D点的这段时间内(包括到达D点的这一刻)，线段PQ与线段AB平行了几次？每一次分别是在出发几秒钟之后？
<gadget id="calculator">12 / 2</gadget>
<output>6</output>

<gadget id="calculator">4 - 1</gadget>
<output>3</output>

<gadget id="calculator">12 / 3</gadget>
<output>4</output>

<gadget id="calculator">1 + 4</gadget>
<output>5</output>

<gadget id="calculator">6 / 5</gadget>
<output>6/5 = around 1.2</output>

<gadget id="calculator">(6/5) + 6</gadget>
<output>36/5 = around 7.2</output>

<result>36/5 = around 7.2</result>