Please choose the correct ending to complete the given sentence: Computers and Electronics: [header] How to relax at the computer [title] Fingers interlaced over the head. [title] Cervical (neck retraction). [step] Put your hand against the temporal area and push the head to the opposite side and hold it with resistance for five seconds.

Ending1: Rest for another five seconds and repeat on the other side [title] Tension at the neck. [step] It's best to sit on a stiff-backed desk. Ending2: [title] Elbows must be in the range of movement for this operation. [title] Believe it or not, we can perform this without thinking, due to safety duty. Ending3: Then, rotate the head to the other side and let the head begin to slide, going slowly away from the body. It should slide out mostly through the back and if you allow the head to slide out all the way, it will move smoothly away. Ending4: Do the same on the opposite temporal, push against it and then push the head back against it with resistance and hold for five seconds. Then put your hand on the forehead and push against the forehead with resistance for five seconds.

Answer format: ending1/ending2/ending3/ending4