Question

3a and c someone please help I really don't understand

Answer 1

F_x=Fcos(a)
F_y=Fsin(a)

1.F_x=166cos(55) 
   F_y=166sin(55)  (55 because of the supplementary angle)

2.F_x= 575cos(-75) (complimentary angle/negative because its under x-axis)
   F_y= 575sin(-75)

The values you get can be negative or positive depending on which side the vector is pointing at.