The inner cavities of bones are filled with 2. the hard, outside part of a bone is called tissue. 3. the spongy, inner tissue of a bone is called tissue. 4. red blood cells are formed in the marrow of bones. 5. the bones are operated by to produce body movements

for me i have felt invisible when i was clearly struggling,or,i made a great achievement ,and,nobody took to notice me either because they just didn't see it,or,people just turned their back on me.i can see a person being invisible by choice,or,without choice like i did.the people who are invisible by choice don't try to talk to people,don't try to make friends,and,keep to themselves.i haven't been one of those people so i couldn't give you a reason.

hope this and can i get bainliest my dude : d