I need help with no. 18. can someone help me? like with how its solved, not just answer

If a(0,0,0) and b(2,2,2) are points in coordinate space, how many paths are there from a to b that move from one lattice point to another in the positive x-,y- or z- direction?

Olga used 100 ounces of flour to make 225 muffins. how many ounces of flour will be used to make 300 muffins?

Which graph represents the equation y =4x