Most houses are not airtight: air goes in and out around doors and windows, through cracks and crevices, following wiring to switches and outlets, and so on$.$ The air in a typical house is completely replaced in less than an hour. Suppose that a moderatelysized house has inside dimensions $12m18m3\mathrm{.}00m$ high, and that all air is replaced in $30\mathrm{.}0$min. Calculate the heat transfer per unit time in watts needed to warm the incoming cold air by $10C,$ thus replacing the heat transferred by convection alone.

At what net rate does heat radiate from a $275-m2$ black roof on a night when the roof's temperature is $30C$ and the surrounding temperature is $15C?$ The emissivity of the roof is $0\mathrm{.}900.$

Three ice cubes are used to chill a soda at $20C$ with mass $m_{\text{s}\text{o}\text{d}\text{a}}=0\mathrm{.}25kg.$ The ice is at $0C$ and each ice cube has a mass of $6\mathrm{.}0g.$ Assume that the soda is kept in a foam container so that heat loss can be ignored. Assume the soda has the same heat capacity as water. Find the final temperature when all ice has melted. Specific heat capacity of water is $4,186\frac{J}{k}g*C$ and latent heat of fusion for water is $334,000\frac{J}{k}g$