The initial temperature of the metal = 35 °C
Heat can be formulated :
Q = m . c . ΔT
Q = heat, J
c = specific heat, J/g C
ΔT = temperature, °C
m = 20 g
c = 5 J/(g°C)
Q = 500 J
T₁ = 40 C
the initial temperature :
[tex]\tt \Delta t(T_2-T_1)=\dfrac{Q}{m.c}\\\\40-T_1=\dfrac{500}{20.5}\\\\40-T_1=5\\\\T_1=35^oC[/tex]