How can flexibility training reduce the risk of back pain? a. it can improve coordination and prevents falls. b. it can improve the poor posture responsible for back pain. c. it can improve body composition, reducing load on the back d. it can increase endorphin levels that reduce pain.

One day, after pulling down your window shade, you notice that sunlight is passing through a pinhole in the shade and making a small patch of light on the far wall. you see that the patch of light seems to be a circular diffraction pattern. it appears that the central maximum is about 1 cm across and you estimate that the distance from the window shade to the wall is about 3 m. what is (a) the average wavelength of sunlight? (b) the diameter of the pinhole?

What is the speed of an object at a given moment?

How to tell if two objects are in thermal equilibrium 1.the objects have the same temperature 2.the objects are the same size 3.the objects are touching each other 4.the objects temperatures are changing