i am struggling to show that for a $n-dim.$ smooth submaifold $M \subset \Bbb R^k$ the normal bundle $NM=\dot \cup_{p\in M}(T_pM)^\bot \subset ι^*T \Bbb R^k\cong M\times \Bbb R^k $ is a smooth rank $(k-n)-dim.$ vektor bundle over $M$.
Where $ι: M \to \Bbb R^k $ denote the inclusion map.
help would be appreciated.