I need help with these questions for my homework. This is all UNIX/Linux material.

1. You can use declare with this option to export a variable name.

2. Simple for-loops are not usually count-controlled in Bash. Instead they are controlled by the length of what?

3. In for-loops with only a control variable and no "in" argument nor list of values, the control variable takes on what values?

4. While and until loops in Bash continue executing based on the outcome of what?