A 100-lbm block of a solid material whose specific heat is 0.5 Btu/lbm·R is at 80°F. It is heated with 10 lbm of saturated water vapor that has a constant pressure of 20 psia. Determine the entropy change of the water. (You must provide an answer before moving on to the next part.) Use data from tables. The entropy change of the water is Btu/R.