Q1. What mass (in grams) of steam at 100°C should be mixed with 257 g of ice at its melting point, in the thermally insulated container, to produce liquid water at 84.0°C?
Q2. A jetliner with an airspeed of 1000 {rm{ km/h}} sets out on a 1600 km flight due south. To continue a southward direction, however, the plane must be pointed 15 ^circ west of south.