Answer
4a. As you move down a group, the general trend of the atomic radius is that it increases down a group.
4b. As you move across a period, the general trend of the atomic radius is that it decreases across a period, as effective nuclear charge increases as electron shielding remains constant.
5. Based on the general trend above, the largest atomic radius would beat the Bottom left corner.
6. Based on the general trend above, the smallest atomic radius would beat the Top right corner.
7. According to the trend described in questions 5 & 6, the following atoms; S, Mg, F, O, and Sr are placed in order of increasing size from smallest to highest.
F is the smallest, O, S, Mg, and Sr is the highest.