Calculate the mass of a piece of copper that released 125 calories when cooled from 100.0 oC to 25.3 oC.

I believe it must be the most.

 q = ms(tf-ti)

s for copper =0.0923cal/g.deg c

  m =??

tf= 100 deg C

ti= 25.3 deg c

Plug in these values in equation
calculate m