Answer: The heat required by iron is 50849.25 Joules or 12152.97 Cal.
Step-by-step explanation:
To calculate the amount of heat released or absorbed, we use the equation:

where,
q = heat absorbed
m = mass of iron = 75 g
c = specific heat capacity of iron = 0.449 J/g.°C
= change in temperature =

Putting values in above equation, we get:

Converting the value from joules to calories, we use the conversion factor:
1 J = 0.239 Cal
So,

Hence, the heat required by iron is 50849.25 Joules or 12152.97 Cal.