Coral reefs grow on submerged platforms of eroded islands eventually forming coral islands called atolls. is this destructive force or constructive force?

None   they are   equally likely to occur on any plate boundary

2pi more meters because you find the circumference which is 6pi and 4pi and subtract it and you get 2pi

Aeolian processes,  pertain to  wind  activity in the study of  geology  and  weather  and specifically to the wind's ability to shape the surface of the  earth  (or other  planets). winds may  erode, transport, and deposit materials and are effective agents in regions with sparse  vegetation, a lack of soil moisture and a large supply of unconsolidated  sediments. although water is a much more powerful eroding force than wind, aeolian processes are important in arid environments such as  deserts