A body starts from rest on a long inclined plane of slope\[45{}^\circ \]. The coefficient of friction between the body and the plane varies as\[u=0.3\text{ }x\], where \[x\]is distance travelled down the plane. The body will have maximum speed (For\[g=10\text{ }m/{{s}^{2}}\]) when \[x=\]

• A. 9.8 m    
• B. 27 m
• C. 12 m    
• D. 3.33 m