there was a warning of volcano eruption in Kilauea in Hawaii. from September 7th to September 8th 2014, the flow advanced about 3/8 kilometers towards the edge of highway 130. the distance (in kilimeters) between the edge of the lava flow and the highway 130 can be given by the function f(t)=6-3/8t where t is the number of days since September 9, 2014. what is the input variables? What are the units of the input variable?