In addition to the trunk release button on the Remote Keyless Entry (RKE) transmitter, the trunk can be opened from inside the vehicle by pressing the remote trunk release button. This button is located inside the driver storage compartment, on the left side of the instrument panel.
See Trunk.
Door Locks
WindowsChevrolet Cobalt Owners Manual. Gasoline Octane
If the vehicle has the 2.2L L4 engine (VIN Code 5),
use regular unleaded gasoline with a posted octane
rating of 87 or higher. If the octane rating is less than
87, an audible knocking noise, commonly referred to
as spark knock, might be heard when driving. If this
occurs, use a gasoline rated ...