(20 10? Suqian) Xiaoming did the experiment of "exploring the imaging law of convex lens" with candles, convex lenses and light screens (as shown in the figure): (1) made it possible to image the candle flame. (1) In the illustrated case, the height of the candle flame center is higher than that of the convex lens and the light screen. In order to make the centers of the three at the same height, the height of the candle flame should be reduced, so the candle moves down.

(2) According to the meaning of the question, when the object distance is 20 cm, the object becomes a real image with the same size. According to the law of convex lens imaging, the object distance at this time is equal to twice the focal length, so the focal length of convex lens is 10 cm.

(3) When the original object becomes an equal real image, the image distance is equal to twice the focal length; When the candle flame moves 2 cm to the right, the object distance at this time is 18 cm, which is one more focal length and two less focal lengths. According to the law of convex lens imaging, the image distance at this time exceeds two focal lengths, so

Move the screen far away, that is, move the screen to the right. At this point, it looks like an inverted enlarged real image.

So the answer is: (1); (2) 10; (3) rights; Zoom in.