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Super! Weight always acts downwards towards the Earth. So, weight must have the downward arrow. The tension on an object is in a direction along the rope, and away from the object. So, the tension must be in the upward direction.
Until now, our co-ordinate system has been: horizontal and to the right is +x, whereas vertical and upwards is +y. For inclined plane problems, it is useful to choose a different co-ordinate system.

The +y directions is perpendicular to the plane and upwards. The +x direction is parallel to the plane, upwards along it.
In this new system, which forces are exactly along the x and which are exactly along the y direction?
  • Normal Force is along +y and Frictional Force is along -x
  • Normal Force is along +y and Frictional Force is along +x
  • Normal Force and Weight are along +y and Frictional Force is along +x
  • Weight is along +y and Frictional Force is along +x