[单选题]
A wooden block slides 0h*g ./pebj6qtay bp6directly down adko 0wioe5o sp,,vrof1 s2n-.n inclined plane, at a constant velocity of 6.0 m5 fsvns1,do0eop-.wk, oio2 r /s. What is the coefficient of kinetic friction, if the plane makes an angle of $25^{\circ}$ with the horizontal?
