A block of mass 47 kg starts at rest at the top of a frictionless ramp that makes an angle of 33.4° below the horizontal. After it slides without friction down the entire 3.38 m length of the ramp, it begins to slide horizontally along a rough concrete surface with a coefficient of kinetic friction of μ?k?? = 0.681 until it slows to a complete stop. How far does the block slide horizontally along the concrete before it stops? [Note: this question may contain more information than is necessary to solve the problem.]