is a binocular cue used to judge distance and depth based on the tension of the muscles that direct where the eyes are focusing.

An important binocular depth cue is convergence, the inward turning of our eyes that is required to focus on objects that are less than about 50 feet away from us. The visual cortex uses the size of the convergence angle between the eyes to judge the object's distance.

Explanation:

enzyme speed up the reactions