Find the average acceleration of a northbound subway train that slows from 12 m/s to 9.6 m/s in 0.9 s
2.7 m/s
-2.7 m/s
2.7 m/s2
-2.7 m/s2

100 grams of molten lead (600°c) is used to make musket balls. if the lead shot is allowed to cool to room temperature (21°c), what is the change in entropy (in j/k) of the lead? (for the specific heat of molten and solid lead use 1.29 j/g⋅°c; the latent heat of fusion and the melting point of lead are 2.45 × 104 j/kg and 327°c, respectively.)