Work, Heat, and q = mcΔT

What is the sign of the work when a gas expands, and why?

What is the work when a gas expands from 3.00 L to 12.60 L against an external pressure of 0.888 atm?

What is the work when a gas contracts from 3.45 L to 0.97 L under an external pressure of 0.985 atm?

True or False: If the heat (q) for a system is positive, the total energy of the system is increasing.

What is the heat when 55.6 g of Fe is warmed from 25.6°C to 177.9°C? (specific heat of Fe = 0.449 J/g·°C)

What is the heat when 245 g of H₂O cools from 355 K to 298 K? (specific heat of H₂O = 4.184 J/g·K)

An unknown mass of Al absorbs 187.9 J of heat as its temperature rises from 23.5°C to 35.6°C (specific heat of Al = 0.897 J/g·°C).
mass = 1($) g