A person whose vision is 20/40 can see an object from 20 feet away that a person with 20/20 vision can see from 40 feet away.
A Snellen chart is a type of eye chart used to assess visual acuity. Snellen charts are named after Herman Snellen, a Dutch ophthalmologist who invented them in 1862. .
A Snellen chart is commonly used to assess visual acuity. Snellen charts show letters getting smaller and smaller. 20/20 is considered "normal" vision. This means that at 20 feet, the test subject sees the same line of letters that a person with normal vision sees at 20 feet.
The Indo-European language is thought to have originated around Azerbaijan and Iran. The Indo-European language is thought to have originated around Azerbaijan and Iran.
