The specific heat of iron is 0.11 cal (g°c) . a cafeteria fork made of iron has a mass of 20 grams. how much heat energy is needed to raise the temperature of this fork from 25°c to 75°c?

The amount of energy needed is 110 calories. We know this by dong the following:
Q=20×0.11×(75−25)
⇒Q=20×0.11×50
⇒Q=110 cal
Bu doing this you have the required heat represented as Q that is supposed to raise the temperature of fork that will be equivalent to the mass multiplied by the specific heat and also by the change in temperature