fix typo

DrModelica/QuickTour/Equations.onb

@@ -31,7 +31,7 @@ p, li { white-space: pre-wrap; }
 <table border="0" style="-qt-table-type: root; margin-top:5px; margin-bottom:5px; margin-left:5px; margin-right:5px;">
 <tr>
 <td style="border: none;">
-&lt;p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;">&lt;span style=" font-family:'Times New Roman'; font-size:12pt; color:#000000;">&lt;br />Equations in Modelica can be classified into three different groups: Normal equations, that occur in equation sections, declaration equations and modification equations. Equations are more powerful than assignments, since one equation can express seceral different assignments.&lt;br />&lt;/span>&lt;/p>&lt;/td>&lt;/tr>&lt;/table>&lt;/body>&lt;/html></Text>
+&lt;p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;">&lt;span style=" font-family:'Times New Roman'; font-size:12pt; color:#000000;">&lt;br />Equations in Modelica can be classified into three different groups: Normal equations, that occur in equation sections, declaration equations and modification equations. Equations are more powerful than assignments, since one equation can express several different assignments.&lt;br />&lt;/span>&lt;/p>&lt;/td>&lt;/tr>&lt;/table>&lt;/body>&lt;/html></Text>
         </TextCell>
         <GraphCell style="Graph" closed="false">
           <Input>class Equations