Step-by-step explanation: the answer is s=16-t², because for this case is really important to keep in mind which is the value with the quadratic expression, when we have a quadratic expression the graphic representation will be a parabola, in a parabola you will find a point that never change which is constant in the diagram.
also keep in mind that the values which are placed in the axis of the ordinates are the independent variables and in parabola the quadratic values are placed in the axis of the ordinates , and for this case is t² because of the quadratic expression, then we can find that t² is the independent variable and s is the dependent variable.
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