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Q=mcdeltaT help!

Hello everyone please help me!

I have been asked to calculate enthalpy change of formation for N2O using data given.

table says:
C + N2O -> CO +N2 -193 KJ mol-1 (not specified whether C or F)
C +1/2O2 -> CO -111 KJ mol-1 (again not specified)

how to do I know whether to draw a Hess' cycle where the arrows point upwards from the elements (formation) or whether to draw one where they point down to combustion products (combustion) IF DONT KNOW WHETHER THE TABLE VALUES ARE FOR COMBUSTION OR FORMATION ENTHALPY CHANGE??? PLEASE HELP ME EVEN MY TACHER COULD NOT EXPLAIN THIS TO ME!!!!!!!!!!! a clear description would help

Can u tell me how to figure out if its a combustion cycle AND ALSO how to figure out if its a formation cycle! thanks!

and secondly,

in Q=MCdeltaT you determine the sign (-/+) by yourself by looking at whether the temperature has increased or decreased. I did a question where two solutions were mixed (NaOH and H2SO4) the temperature went from 20 degrees and rose to 29 degrees. The answer in the book said use a + sign as it's endothermic? can someone explain this?

another question mixed solid iron powder to copper sulphate in a polystyrene cup. The sign here needed was - when the temperature went from 21 to 25 degrees? here the temperature s increased but the sign is - , why is it EXOTHERMIC NOW??? I am so confused please explain clearly thanks.