The heat absorbed is calculated with the help of the formula,
Q = mCΔT
Q is heat absorbed, m is mass given as 56 gms, C is the specific heat of iron, that is, 0.449 J/g°C, and delta T is the change in temperature, which is 28 - 7 = 21°C
Thus, Q = 56 × 0.449 × 21 = 528 J