Calculating Linear Expansion with Specific Heat Capacity and Mass Density?

[Kara4566]

Homework Statement

A 1.0m long rod of metal has a diameter of 0.75cm. This metal has
a coefficient of linear expansion α = 4.8 × 10−5 1/K, a density of 9.7 ×10^3 kg/m^3, and heat capacity of 390 J/K.
How much energy needs to be added as heat to increase the length of the rod by 7.5 × 10−3m?

Relevant Equations

change in Length= (Initial Length)(Coefficient of linear expansion)(change in temperature)

Above is my attempt at a solution, however, this did not yield the correct answer. Any help is greatly appreciated!

 

[TSny]

I wonder if the heat capacity of 390 J/K is really meant to be a specific heat capacity of 390 J/(kg K). Then, you can make use of the mass density given in the problem.