4. (15 points) Determine the moment of the force about point O. Assume F= 300 N. Express your answer to three significant figures and include the appropriate units. 0.4 m 45° 0.3 m 30° F Study Examples 4.5 and 4.6 and Problem 4-21. Is it necessary to define the x-y coordinates? 6+ ANSWER: Mo= Fsin () (0.4+0.3cos ()) - Fcos (1) -0.3sin()=45.3N-m