If $\overline{\mathrm{a}}\text{ = }\overline{\mathrm{b}}$, then which of the following is NOT correct? 

• A

  $\widehat{\mathrm{a}}\text{ = }\widehat{\mathrm{b}}$

• B

  $\left|\overline{\mathrm{a}}\right|\text{ = }\left|\overline{\mathrm{b}}\right|$

• C

  $\mathrm{b}\widehat{\mathrm{a}}\text{ = a}\widehat{\mathrm{b}}$

• D

  $\overline{\mathrm{a}}\text{ + }\overline{\mathrm{b}}=\widehat{\mathrm{a}}+\widehat{\mathrm{b}}$