Normal vision is called 20-20 vision. these numbers are actually a ratio—a comparison of the distance you can see to the distance a normal-sighted person can see. for example, a person with 20-30 vision can see from a distance of 20 feet what a person with 20-20 vision can see from a distance of 30 feet. based on this knowledge, explain what the following numbers mean regarding vision.
a. 20-100
b. 20-40

See below.

Step-by-step explanation:

a. A person with 20-100 vision can see  from a distance of 20 feet what a person with 20-20 vision can see from 100 feet.

b. If you have 20-40 vision you can see from 20 feet what a person with 20-20 vision can see from 40 feet.

a28=58

step-by-step explanation:

a1=a1+(n-1)d

a28= 4+ (28-1)2

a28=4+(27)(2)

a28=4+54

a28=58

b. ol

step-by-step explanation:

i got the answer right on edg.

congruent: (geometry) (of figures) identical in form; coinciding exactly when superimposed.