An ornamental pond is $0\mathrm{.}8$ m deep and has a surface area of $100$ m$2.$ If the sunlight falling on the pond transfers energy to the surface of the pond at an average rate of $200$ watts$/$m$2,$ find the time it will take to raise the temperature of the pond from $41$o F to $68$o F$.$ Assume that all of the heat absorbed by the water remains in the water.