Line l1, l2 and l3 are in the same plane, l1 is perpendicular to l2, and l3 is parallel to l1. which of the following statement must be true? 1. l3 is parallel to l2 2.l3 is perpendicular to l2 3.l3 intersects l2

Only Statement 2 is surely correct.
because there maybe chances that the line L1 and L3 lies above the line L2 and they can also fulfill the condition of perpendicularity so we can't be sure about statement 3 & statement 1 is clearly incorrect

If gravity is one third on mars then weight also one third on mars