The teacher and we took a picture of graduation photo as a souvenir.

(1) The working principle of the camera is to use a convex lens to form an inverted and reduced real image; When the camera images, the image distance is greater than 1 times and the focal length is less than 2 times. Therefore, the focal length of the camera lens is 60mm, and the distance between the negative and the lens is between 60 mm-120 mm. Because the object distance is large and the image distance is small when shooting the ground scene on the plane, the bottom is closer to the focus position.

(2) From B to A, the image becomes larger, the object distance becomes smaller, and the image distance becomes larger. So before pressing the shutter, the camera should be close to the classmates and the lens should be extended forward.

So the answer is: (1) the convex lens is inverted and reduced; d； (2)① The camera is close to the classmates; ② The lens stretches forward.