1. The problem statement, all variables and given/known data A 5.0-kg piece of lead at a temperature of is 600 Celsius placed in a lake whose temperature is 15 Celsius. Determine the entropy change of (a) the lead piece, (b) the lake, and (c) the universe. mass of lead=5 kg initial temperature of lead=873.15 K final temperature of lead=288.15 assumed that the temperature of lake wont noticeably change) heat capacity of lead=128 J/(kg⋅K) 2. Relevant equations For the lead, ΔS=mass of lead⋅heat capacity of lead⋅ln(final temperature/initial temperature) For the lake and the universe im not sure where to begin. 3. The attempt at a solution For the lead I got ΔS=-710 J/K The books answer is ΔS=-540 J/K for the lead. I feel like the book isn't giving all of the necessary data to solve this problem (i.e. the size of the lake).