What skills did both hassan and his son sohrab possess? how did this skill prove to be so vital for amir to accomplish his mission? \?

The kite runner written by Khaled Hosseini is a time-depicting and interesting novel. For Amir Sohrab is like a young version of his father. However, we can say that both suffer from ethnic discrimination  and the skills that they have in common is that both felt attraction for books. The skill that proved to be vital for Amir to accomplish his mission was running kites because at the end of the story it let him get closer to Sohrab.  

the invasive species was introduced due to commercial purpouses, as there was a demand for fur clothes and hence, a business opportunity connected to this product. actually, it was when the nutrias scaped, causing harm to the us ecosystems when they acquired the status of invasive species. in this case they have caused an environmental problem, but it could have affected also economic interests or even human health.