Normal vision is 20/20 vision, or in metric 6/6. This means that when you are 20 feet away from something, you will see what someone with normal vision would see at 20 feet away. With 20/40 vision, you would see something 20 feet away as someone with normal vision would see it at 40 feet, so therefore it would be blurry. 20/100 is also possible and 20/200 is considered legal blindness. 20/10 would be better than normal. (Adapted from howstuffworks.com)
Assuming that the man who has normal vision is homozygous for normal vision, the couple's daughter will either be homozygous for normal vision or heterozygous (normal vision but carrier for color blindness) for normal vision. In light of this, the couple's daughter will not be color blind.
Development goals for a country is usually dictated by its leaders and the vision that they have for their countrymen.
which of the following indicates normal vision at 20 feet
It is not impact our vision.
Emmetropia
Emmetropia is basically normal vision, or a state of vision in which far objects are in sharp focus, with the eye lens in a normal state.
30 50 is considered mild vision loss, or near-normal vision.
Peripheral vision is the type of vision that is useful in sensing motion and objects outside of normal vision range. It allows us to detect movement and objects in our surroundings without directly looking at them.
Usually a Snellen's Chart is used to assess vision.
It means seeing at 20 feet what a person with normal vision sees at 20 feet. A person who has 20/40 vision can see at 20 feet what the person with normal vision sees at 40 feet, etc. Some people have better than 20/20 vision.
50%
scotoma