The heat that is required to raise the temperature of an object is calculated through the equation,
            heat = mass x specific heat x (T2 - T1)
Specific heat is therefore calculated through the equation below,
                specific heat = heat / (mass x (T2 - T1))
Substituting,
                specific heat = 645 J / ((28.4 g)(15.5 - - 11.6))
The value of specific heat from above equation is 0.838 J/g°C.Â