3. A complex object is made of two identical pieces of steel, 2x1cm, arranged in the shape of a 'T' (top figure). a) Calculate the x distance of the CM of the complete object from the leftmost edge (XCM) b) If another identical piece is added as shown in the lower figure, find the new XCM 4. Two masses, 30kg & 20kg are on opposite ends of a wooden plank 2m long which itself has a mass of 5kg. a) How far from the edge of the plank below the 30kg mass is the CM of the system? 30 b) Recalculate the CM position assuming the plank has no mass 20