Alphametic Warmup

Find the range of each letter in bold:

A + B = C
A − B = C
A + B = CD
AA + B = CD
AA + B = CDE
A × B = C
A × B = CD
AA × BB = CDE
AA × BB = CDEF

Find the unique solution

SEND + MORE = MONEY
SMART + MOVE = DOCTOR
TRIAL + ERROR = ASSURE
SMART + MIRACLE = SUCCESS