Inside Trunk Release Lever
Adults are advised to familiarize themselves with the operation and location of the inside trunk release lever so that all children can be told about it in an appropriate way, keeping in mind that most vehicles do not have such levers.
WARNING:Close the trunk lid, be sure the seat backs are latched and do not allow children to play inside the vehicle: Leaving the trunk lid open or leaving children in the vehicle with the keys is dangerous. Children could open the trunk lid and climb inside resulting in possible injury or death from heat exposure.
Always keep the car from being a tempting place to play by latching the rear seats, doors and the trunk, and keeping the keys where children can not play with them:
Leaving children or animals unattended in a parked vehicle is dangerous. Babies left sleeping and children who lock themselves in cars or trunks can die very quickly from heat prostration. Do not leave your children or pets alone in a car at any time. Do not leave the car, the rear folding seats or the trunk unlocked.
Slide the inside trunk release lever in the direction of the arrow. The lever is made of material that will glow for hours in the darkness of the trunk following a brief exposure to ambient light.

The inside trunk release lever is located on the inside of the trunk lid.
Test yourself
A quick Mazda 6 quiz: every answer comes with an explanation and a link to the manual page.