HELP PLEASE!! :) (2)Compute the x and y coordinates of the centre of mass of the piece. => i'm not sure what steps are to computing coordinates. I have a cartesian plane with a block shaped 'C'... Do i just break it down into geometric shapes (i.e. rectangles/squares) and compute the CM of each one, then what do i do to get the CM of the total block? (3) A 40 kg box initally at rest is pushed 5.00m along a rough, horizontal floor with a constant, applied horizontal force of 130 N. If the coefficient of friction between box and floor is 0.300, find: (a) the work done by the applied force (b) increase in internal energy in the box-floor system due to friction => I know w=u*Fn*d to find work due to friction, how do i go by finding the INCREASE in internal energy?... kinetic energy = 1/2mv^2? (c) the work done by normal force (d) the work done by gravitational force => for Wg=mgdcos(theta)... is thetha perpendicular (90 degrees) to horizontal? (e) the change in kinetic energy of the box =>change in kinetic energy of box, equals Ek after - Ek before... how can i solve for this if i dont know the final velocity? (f) the final speed of the box => conservation of kinetic energy is used?