10 Oct A ?delivery truck with a flat bed drives around the city of San Francisco, ?which is famous for its steep hills. The truck carries a crate on its ?bed. Unwisely, the driver
A delivery truck with a flat bed drives around the city of San Francisco, which is famous for its steep hills. The truck carries a crate on its bed. Unwisely, the driver has not secured the crate to the bed, so the crate merely rests...