WPF StrokeStartLineCap Flat,Square,Round,Triangle

<Window x:Class="WpfApp74.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WpfApp74"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="800">
    <Grid>
        <Grid.ColumnDefinitions>
            <ColumnDefinition/>
            <ColumnDefinition/>
            <ColumnDefinition/>
            <ColumnDefinition/>
        </Grid.ColumnDefinitions> 
        <Polyline Grid.Column="0"
                  Points="50,50,75,30,100,100,130,40"
                  Stroke="Red"
                  StrokeThickness="20"
                  StrokeStartLineCap="Flat"
                  StrokeEndLineCap="Flat"
                  ToolTip="Flat"
                  /> 
        <Polyline Grid.Column="1"
                  Points="50,50 75,30 100,100 130,40"
                  Stroke="Red"
                  StrokeThickness="20"
                  StrokeStartLineCap="Square"
                  StrokeEndLineCap="Square"
                  ToolTip="Square"
                 /> 
        <Polyline Grid.Column="2"
                  Points="50,50 75,30 100,100 130,40"
                  Stroke="Red"
                  StrokeThickness="20"
                  StrokeStartLineCap="Round"
                  StrokeEndLineCap="Round"
                  ToolTip="Round"/> 
        
        <Polyline Grid.Column="3"
                  Points="50,50 75,30 100,100 130,40"
                  Stroke="Red"
                  StrokeThickness="20"
                  StrokeStartLineCap="Triangle"
                  StrokeEndLineCap="Triangle"
                  ToolTip="Triangle"/>
    </Grid>
</Window>