Einen is a German word in feminine form that means an. I hope this helps
Electronic configuration of calcium ion would be same as Argon..
1s2, 2s2 2p6 3s2 3p6
"I am sometimes stressed because I have a lot of homework to do. When I am stressed I become tired or I have a headache" in german is:
Ich werde manchmal betont, weil ich viel Heimarbeit habe, zum zu tun. Wenn ich betont ich werde müde bin oder, ich habe Kopfschmerzen
Hope I Helped!!!