How the image of a convex lens changes

A convex lens has a focal length of $13\ \text{cm}$. You will make the program find the image for five object distances, pick out the distance that gives an image of the same size, and count the images smaller than the object. Then it draws the image distance and the size of the image.

Your tasks.

1. Inside the loop, work out v and m for the object distance d.
2. Find same, the object distance that gives an image of the same size.
3. Find smaller, how many of the images are smaller than the object.