"Solve:
(a )
<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}-->
23 +
<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}-->
34 +
<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}-->
12
(b) 423 + 3
<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}-->
14