Please help as much as you can with explanations.

Suppose a certain person's visual acuity is such that he or she can see objects clearly that form an image 4.00 mm high on his retina. What is the maximum distance at which he can read the 85.0 cm high letters on the side of an airplane? The lenstoretina distance is 2.00 cm. A typical human eye is nearly spherical, and is usually about 2.5 cm in diameter. Suppose a person rst looks at a coin that is 2.0 cm in diameter and located 27.0 cm from her eye. Then, she looks up at a friend who is 1.8 m tall and 3.75 m away. Find the magnitude of the approximate size of each image (coin h1,coin and friend h1,friend) on her retina. (Hint: Just consider rays from the top and bottom of the object that pass through the center of the lens.) h1,friend = cm hI'COi = cm