Fill in the blanks to make the statement true.
Alternate interior angles have one common __.
Two alternate interior angles have one common arm.
Fill in the blanks to make the statements true.
The common properties in the two set squares of a geometry box are that they have a ___ angle and they are of the shape of a ___.
The digit having only one line of symmetry is ___.
___ is the multiplicative identity for integers.
Two angles are said to be ______ if they have equal measures.