Laura runs during her lunch break. The average speed SSS, in kilometers per hour, at which Laura runs depends on the temperature ttt, in degrees Celsius (^{\circ}\text{C})(
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C)left parenthesis, degrees, start text, C, end text, right parenthesis, at the start of her run and can be modeled by the function S(t)=6+0.2(25-t)S(t)=6+0.2(25−t)S, left parenthesis, t, right parenthesis, equals, 6, plus, 0, point, 2, left parenthesis, 25, minus, t, right parenthesis.
The distance, DDD, in kilometers, that she can run in 303030 minutes given that her average speed is xxx kilometers per hour can be modeled by the function D(x)=0.5xD(x)=0.5xD, left parenthesis, x, right parenthesis, equals, 0, point, 5, x.
Which expression models the distance that Laura runs in 303030 minutes given that it is t^\circ{\text{C}}t
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Ct, degrees, start text, C, end text outside at the start of her run?