Question

13. When processing all the elements of a column of a two-dimensional array, what possible runtime error do we have do worry about that the number of column elements may not be constant across all rows.

Answer 1

In JAVA Multi-dimensional arrays are built frommultiple one-dimensional arrays.
Two-dimensional array might look like:
[1][2][3]
[1][2][3]
or
[1][2]
[1][2][3][4]

The most common runtime erroris: ArrayIndexOutOfBoundsException