The amount of energy that was used to heat Cu is 27.6 cal
calculation
Heat (Q) = M ( mass) x c(specific heat capacity) x ΔT( change in temperature)
where;
Q=?
M = 5.0 g
C=0.092 cal/g°C
ΔT = 80°c-20°c=60°C
Q is therefore = 5.0 g x 0.092 cal / g°c x 60°c =27.6 cal