o level chem prac sos

for temperature rise/decrease, do we need to add the +/-? my cher insists that we need but other school prelim paper says that students were penalised for indicating it....

for titration, EXAMPLE: if the avg vol is 25.45cm^3. and during calculation they give us mr is 148. and we're required to take 25.45 x 148. do we leave ans in 3 sf or 4sf? since 148 is given data and 25.45 is processed data...

THANK YOU IN ADVANCE SM YALL. chem prac is literally tmr :(