What are the three principles of good posture?

Here's the There are two types: Dynamic posture is how you hold yourself when you are moving, like when you are walking, running, or bending over.  Static posture is how you hold yourself when you are not moving, like when you are sitting, standing, or sleeping.

Your Spine: Good posture actually means keeping the three curves of your spine in balanced alignment. ... Strong and flexible muscles also are essential to good posture. Abdominal, hip, and leg muscles that are weak and inflexible cannot support your back's natural curves. Your Joints.

Explanation:

when comparing the cases, what similarities are there in the cases that suggest one person committed these murders?