From reliable sources in the web, it may be searched that the specific heat of copper is approximately equal to 0.385 J/gC. The amount of heat that is required to raise a certain amount by certain number of degrees is given in the equation,
H = mcpdT
where H is heat, m is mass, cp is specific heat, and dT is temperature difference. Substituting the known values,
186,000 J = (m)(0.385 J/gC)(285C)
m = 1695.15 g