\documentclass{article}
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\usepackage{setspace}
\usepackage{multicol}
\usepackage{fontspec}
\usepackage{ulem}
\usepackage{tikz}
\usetikzlibrary{er,positioning,shapes.symbols}

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%% METADATEN HIER
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\newcommand{\blattnr}{1} % Blattnummer
% Person 1
\newcommand{\authorAVorname}{Max} % Vorname
\newcommand{\authorANachname}{Mustermann} % Nachname
\newcommand{\authorAMatrikelnummer}{1234567} % Matrikelnummer
% Person 2
\newcommand{\authorBVorname}{Maria} % Vorname
\newcommand{\authorBNachname}{Musterfrau} % Nachname
\newcommand{\authorBMatrikelnummer}{2345678} % Matrikelnummer
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\newcommand{\fach}{Modellierung SoSe2017} % Ggf. Semester / Fach hier anpassen

%% Hilfsmakros
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\usepackage[noenc]{tipa}
\usepackage{tipx}
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\usepackage{pifont}
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\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amssymb,amsfonts,textcomp}
\usepackage{color}
\usepackage{array}
\usepackage{supertabular}
\usepackage{hhline}
\usepackage{hyperref}
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\makeatletter
\newcommand\arraybslash{\let\\\@arraycr}
\makeatother

\fancypagestyle{firststyle}{
	\fancyhf{}
	\fancyhead[L]{\fontsize{10pt}{0pt}
		\fontspec[LetterSpace=5]{Arial}
		 Modellierung Sommersemester 2017}
	\renewcommand{\headrulewidth}{0pt}
}

\tikzset{
	hexagon/.style={signal,signal to=east and west}
}

\begin{document}
	\normalem
	%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
	% BEGIN DECKBLATT
	%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
	\fontsize{12pt}{20pt}
	\fontspec[LetterSpace=5]{Arial}
	\setlength{\parindent}{0pt}
	\thispagestyle{firststyle}
	\setstretch{2}
	\clearpage\setcounter{page}{1}
	\vspace*{-3em}
	{\large Aufgabenblatt \blattnr}
	\vspace*{-2em}
	\begin{flushleft}
		\tablefirsthead{}
		\tablehead{}
		\tabletail{}
		\tablelasttail{}
		\begin{supertabular}{|m{5.1270003cm}|m{5.129cm}|m{5.129cm}|}
			\hline
			\vspace*{-1em}Name &
			\vspace*{-1em}Vorname &
			\vspace*{-1em}Matrikelnummer\\\hline
			\authorANachname &
			\authorAVorname &
			\authorAMatrikelnummer\\\hline
			\authorBNachname &
			\authorBVorname &
			\authorBMatrikelnummer\\\hline
		\end{supertabular}
	\end{flushleft}
	\vspace*{-0.5em}Die Bearbeitung der Aufgabenblätter muss durch zwei in Ilias registrierte Mitglieder des\\\vspace*{-1.2em}Kurses „Modellierung (SS17)“ erfolgen.


	\bigskip

	\hspace*{-\parindent}In der folgenden Tabelle werden die erzielten Punkte eingetragen.\vspace*{-2.5em}
	\setstretch{2.5}
	\begin{flushleft}
		\tablefirsthead{}
		\tablehead{}
		\tabletail{}
		\tablelasttail{}
		\begin{supertabular}{|m{2.042cm}|m{5.129cm}|m{8.223001cm}|}
			\hline
			\vspace*{-1em}\centering Aufgabe &
			\vspace*{-1em}\centering Erreichte Punkte &
			\vspace*{-1em}\centering\arraybslash Bemerkungen zur Korrektur\\\hline
			\vspace*{-1em}\centering 1 &
			~
			&
			~
			\\\hline
			\vspace*{-1em}\centering 2 &
			~
			&
			~
			\\\hline
			\vspace*{-1em}\centering 3 &
			~
			&
			~
			\\\hline
			\vspace*{-1em}\centering 4 &
			~
			&
			~
			\\\hline
			\vspace*{-1em}\centering 5 &
			~
			&
			~
			\\\hline
			\vspace*{-1em}\centering 6 &
			~
			&
			~
			\\\hline
			\vspace*{-1em}\centering 7 &
			~
			&
			~
			\\\hline
			\vspace*{-1em}\centering 8 &
			~
			&
			~
			\\\hline
			\vspace*{-1em}\raggedleft Gesamt: &
			~
			&
			~
			\\\hline
		\end{supertabular}
	\end{flushleft}

	\bigskip
	\pagebreak
	\normalsize
	\normalfont
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	\setstretch{1}
	\setcounter{page}{1}
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	% END DECKBLATT
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	\title{\gettitle}
	\author{\renewcommand*\AND\and\authors}
	\maketitle
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	%% AUFGABEN HIER:
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	\aufg{1}
	\asubaufg{a}
	Aufgabe 1a hier
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\end{document}