The rental agencies determine the rules for that. Most rental companies will not rent to anyone under the age of 25. Some will rent to people 21 to 24 years old, but charge a premium rate. The only time I have ever heard of a rental car company renting to an 18-year old is to a member of the military.
1 The lens is a soft, transparent, spherical structure that is suspended within the eye, just behind the pupil. 2  The lens is responsible for focusing light coming in through the pupil onto the retina in the back of the eye.
Pupil (eye) The pupil is the opening in the centre of the eye. Light enters through the pupil and goes through the lens, which focuses the image on the retina. The size of the pupil is controlled by muscles. There is a circular group, which squeezes the iris smaller, and another group which pulls the iris wider. When more light is needed, the pupil is made larger. In brighter light, the pupil is made smaller. The pupil can be compared with the shutter of a camera. It is surrounded by the iris which is the coloured part of the eye. The lens changes its shape depending on how far away the eye focuses. The focus point is where the eye is focusing on. The light makes the pupil change its size.