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A student uses a pencil as a lever to launch a piece of trash into the trashcan. If the student positions a marker as the fulcrum just 2.8 cm from where she applies effort, and 7 cm from the piece of trash to the fulcrum, what is the mechanical advantage the lever gives?

Use the profile illustrated for problem (1). assume that the layer of silty sand fill (sm) is placed over the entire site. estimate the thickness of the fill (h - in feet) that will cause the effective vertical stress at the center of the clay layer to increase by 517.5 pounds per square foot.