30 CM one because the light gathering power will be better
Explanation:
Based on the information provided within the question it can be said that in this scenario the best option that you can choose from would be the 30 CM one because the light gathering power will be better on that one as opposed to the 20cm one. In telescopes the larger the lens, the clearer the image will be as it allows more light to enter and cause the image to be sharper.
Iconic memory could be described as the visual sensory memory register regarding the visual domain and a fast decaying store of visual information. It also includes visual short-term memory and long term memory. It is the imagination of an item in the mind and it also supports long and short term memory.
