If H.C.F.(a,b)=9 and a.b=100, then L.C.M.(a,b)=
In the given figure, AB||CD. If ∠AOC=30∘ and ∠OAB=100∘ then ∠OCD=?
(a)130∘
(b)150∘
(c)80∘
(d)100∘