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4. The temperature of the water in a pond is modeled by a differenliable function T for 0 g t 1:15, where t is measure in days and w\") is measured in degrees Celsius. Values of W [3) at selected values of t are shown in the table below. [c] Use data from the table to nd an approximation for W17} Show the computations that lead to your answer. [d] Based on values in the table, what is the smallest number of instances at which the temperature of the pond could equal 23C on the open interval I]