(a) Use a scalar projection to derive the formula la$+bg cl which is the distance between the point (5:, 37) and the line ax + by = c. (b) Use the cross product to derive the distance formula between the point Q and the lin l e l@ x Pfa IP31 where the points P and R are in the line l. (c) Find the distance between the point (2,1) and the line 2:c + 53; = 7. (d) Find the distance between the point (2,1, 1) and the line a:=1+2t y=7+3t z=1+4t