A cyclist starts from the centre O of a circular park of radius 1 km, reaches the edge P of the park, then cycles along the PQ circumference and returns to the centre along QO as shown in the figure. If the round trip takes ten minutes, the net displacement and average speed of the cyclist (in kilometre and kilometer per hour) is

 

• A

  0, 2($\mathrm{\pi }+4$)

• B

  $\frac{\mathrm{\pi }+4}{2}, 0$

• C

  $21.4, \frac{\mathrm{\pi }+4}{2}$

• D

  0, 3($\mathrm{\pi }+4$)