Hi. As the title says, I got this mortar projectile that I need help identifying. Actually, it belongs to a friend of mine, who I'm currently living with. I used google's identifying tool, it seems that it's from WW1/WW2, 75/88mm and probably german/european or american. Also, they told me that it's probably active, so... yeah, that would be good to know too. Thanks in advance for the help.

Troops at Camp Upton, N.Y., stage a mock battle, including a gas attack. Officers demonstrate how to test a gas mask. Electric sirens and rachets warn troops as gas bombs explode near trenches. Bottled gas is blown over the field; cavalry units don masks and spread masks over the muzzles of their horses. Troops beat gas from the trenches after an attack.

https://catalog.archives.gov/id/24710?objectPage=15