Diagonals of a parallelogram $\mathrm{A}\mathrm{B}\mathrm{C}\mathrm{D}$ intersect at $\mathrm{O}$. If $\mathrm{\angle }\mathrm{B}\mathrm{O}\mathrm{C}=90°$ and $\mathrm{\angle }\mathrm{B}\mathrm{D}\mathrm{C}=40°$. Then what is the measure of $\mathrm{\angle }\mathrm{O}\mathrm{A}\mathrm{B}$?

In the statement, ''If three angles of a quadrilateral $\mathrm{A}\mathrm{B}\mathrm{C}\mathrm{D}$ are equal, then it is a parallelogram.''

True, False, May or may not be true.