for first part

no of reigions=no of quads formed by intersecting lines+2(n-1)i.e small triangles at ends +1(gap in bet. these two reigons of small triangles)+2(n-1)(extra quads formd by lines and resp. side+2(two other small triangles+1(big upper quad)

=nC2XnC2+4(n-1)4+4

=(nC2)+4n

plzzzzzzzz make second part clear

how can 3diff lines mett at two pts

draw fig you will get yaar!!!

rate me if rite!!!!!!!!!!!!!!!!!!