Perl Variables for Numerical Questions

The following reserved Perl variables are used to return information or set behaviors in questions that you create in WebAssign.

Variable	Description
`$DECFIGS`	Sets the required decimal places, for example, `$DECFIGS=100` or `$DECFIGS=0.01`.
`$SIGFIGS`	Sets the required number of significant figures as a positive integer, for example, `$SIGFIGS=3`.
`$NO_SIGFIGS_HINT`	Hides the significant figures help icon/link.
`$FRACTION`	Set `$FRACTION=1` to require students to perform computations and accept only exact answers as integers, decimals, fractions, or mixed numerals.
`$PROPERFRACTION`	Set `$PROPERFRACTION=1` to require students to perform computations and accept only exact answers as integers or reduced fractions.
`$SIMPLIFIED`	Set `$SIMPLIFIED=1` to require students to perform computations. Otherwise, students can enter either `5` or `2+3`. Students can specify proper or improper fractions, for example, `10/2`.
`$size`	Sets the width of the answer box, for example, `$size=20`.
`$thisnum`	Returns numerical value from student's response to numerical with units question. Important Changing the value of this variable can cause your student's answer to be graded incorrectly.
`$thisunit`	Returns unit from student's response to numerical with units question. Important Changing the value of this variable can cause your student's answer to be graded incorrectly.
`$TOL`	Sets asymmetrical tolerances. For example: `$TOL={min => 0, max => 4}`
`$LABEL`	For answer-dependent questions, set $LABEL to a unique identifier for each answer box that is used as a dependency for another answer box.
`$LINK`	For answer-dependent questions, set $LINK to define the dependencies of the current answer box by referencing the labels of other answer boxes.