What is the meaning of the word "specialist" in the sentence,"she is a specialist at the stock exchange."

These two elements threaten ecosystem biodiversity.

)claim: kids benefit from their time plugged into devices like tvs, tablets, and smartphones. which presents an alternative, or different, view on this topic? a) preschoolers often get learning the alphabet on public television shows. b) teens can conduct research on any subject using credible sources on the internet. c) elementary school children can play educational apps and games on tvs, tablets, and smartphones. d) middle school children sometimes copy negative behaviors of characters on tv and in video games, such as smoking and drinking.

What time of year are the northern lights visible?