Misc: who was the director of the fbi from 1924 to 1974?

Questions

If you cut through a solid sphere what shape will the flat area be?

Name the number system which uses only the symbols 1 and 0.?

The angles inside a square total _______ degrees.?

The mathematical study of properties of lines, angels, etc., is ________.?

The space occupied by a body is called its ______.?