The latent heats for some substances are given below.
substance latent heat of fusion j/kg latent heat of vaporization j/kg
lead 0.25 e⁵ 8.68 e⁵
mercury 0.12 e⁵ 2.7 e⁵

how much heat is needed to melt 15.0 kg of lead at its melting point?
a. 1.80 e⁵ j
b. 3.75 e⁵ j
c. 4.05 e⁶ j
d. 1.30 e⁷ j