diff --git a/Lectures/L04_ReqContinued/ReqContinued.pdf b/Lectures/L04_ReqContinued/ReqContinued.pdf
index a7762d7da970718c02dd95db568aba3e595d2ec1..9d9b579acdb961c24e9f56d59b78b00f4ff24a0c 100644
Binary files a/Lectures/L04_ReqContinued/ReqContinued.pdf and b/Lectures/L04_ReqContinued/ReqContinued.pdf differ
diff --git a/Lectures/L04_ReqContinued/ReqContinued.tex b/Lectures/L04_ReqContinued/ReqContinued.tex
index 7c0d70e6065d93a3308419c313da7294d3c3215b..3fd79ff6a7c4d07de1ed92bb851dd81a6969e677 100755
--- a/Lectures/L04_ReqContinued/ReqContinued.tex
+++ b/Lectures/L04_ReqContinued/ReqContinued.tex
@@ -143,7 +143,7 @@ Final Documentation & Week 13 & Dec 6\\
 
 \bi
 \item 3 presentations each
-\item Presenations are about 30 minutes, except for MG, which is 15 minutes
+\item Presentations are about 30 minutes, except for MG, which is 15 minutes
 \item Grading out of 3
 \bi
 \item Generate discussion, evidence of prior thought, organized 3/3
@@ -797,277 +797,6 @@ to improve reliability
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
-\begin{frame}
-\frametitle{Specification Qualities}
-
-\begin{itemize}
-
-\item \structure{What are the important qualities for a specification?}
-
-\end{itemize}
-
-\end{frame}
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-
-\begin{frame}
-\frametitle{Specification Qualities}
-
-\begin{itemize}
-\item The qualities we previously discussed (usability, maintainability,
-  reusability, verifiability etc.)
-\item Clear, unambiguous,  understandable
-\item Consistent
-\item Complete
-\begin{itemize}
-\item Internal completeness
-\item External completeness
-\end{itemize}
-\item Incremental
-\item Validatable
-\item Abstract
-\item Traceable
-\end{itemize}
-
-Summarized in \cite[p.\ 406]{SmithAndKoothoor2016}
-
-\end{frame}
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-
-\begin{frame}
-\frametitle{Clear, Unambiguous, Understandable}
-
-\begin{itemize}
-
-\item Specification fragment for a word-processor
-\begin{itemize}
-\item \structure{Selecting is the process of designating 
-areas of the document that you want to 
-work on. Most editing and formatting 
-actions require two steps: first you 
-select what you want to work on, 
-such as text or graphics; then you 
-initiate the appropriate action.}
-\end{itemize}
-\item What are the potential problems with this specification?
-\begin{itemize}
-\item<2-> {\alert{Can an area be scattered?}}
-\item<2->{\alert{Can both text and graphics be selected?}}
-\end{itemize}
-\end{itemize}
-
-\end{frame}
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-
-\begin{frame}
-\frametitle{Clear, Unambiguous, Understandable}
-
-\begin{itemize}
-
-\item Specification fragment from a real safety-critical system
-\begin{itemize}
-\item \structure{The message must be triplicated. The three
-copies must be forwarded through three 
-different physical channels. The receiver 
-accepts the message on the basis of a 
-two-out-of-three voting policy.}
-\end{itemize}
-\item What is a potential problems with this specification?
-\begin{itemize}
-\item<2-> {\alert{Can a message be accepted as soon as we receive 2 out of 3 identical copies, or do we need to wait
-for receipt of the 3rd}}
-\end{itemize}
-\end{itemize}
-
-\end{frame}
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-
-\begin{frame}
-\frametitle{Unambiguous, Validatable}
-
-\begin{itemize}
-
-\item Specification fragment for an end-user program
-\begin{itemize}
-\item \structure{The program shall be user friendly.}
-\end{itemize}
-\item What is a potential problems with this specification?
-\begin{itemize}
-\item<2-> {\alert{What does it mean to be user friendly?}}
-\item<2-> {\alert{Who is a typical user?}}
-\item<2-> {\alert{How would you measure success or failure in meeting this requirement?}}
-\end{itemize}
-
-\end{itemize}
-
-\end{frame}
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-
-\begin{frame}
-\frametitle{Unambiguous, Validatable}
-
-\begin{itemize}
-
-\item Specification fragment for a linear solver
-\begin{itemize}
-\item \structure{Given $A$ and $b$, solve the  linear system $A x = b$ for $x$, such that the error in any entry of
-$x$ is less than 5 \%.}
-\end{itemize}
-\item What is a potential problems with this specification?
-\begin{itemize}
-\item<2-> {\alert{Is $A$ constrained to be square?}}
-\item<2-> {\alert{Can $A$ be singular?}}
-\item<2-> {\alert{Even if the problem is made completely unambiguous, the requirement cannot be validated.}}
-\end{itemize}
-
-\end{itemize}
-
-\end{frame}
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-
-\begin{frame}
-\frametitle{Consistent}
-
-\begin{itemize}
-
-\item Specification fragment for a word-processor
-\begin{itemize}
-\item \structure{The whole text should be kept in lines 
-of equal length. The length is specified 
-by the user. Unless the user gives an 
-explicit hyphenation command, 
-a carriage return should occur only 
-at the end of a word.}
-\end{itemize}
-\item What is a potential problems with this specification?
-\begin{itemize}
-\item<2-> {\alert{What if the length of a word exceeds the length of the line?}}
-\end{itemize}
-
-\end{itemize}
-
-\end{frame}
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-
-\begin{frame}
-\frametitle{Same Symbol/Term Different Meaning}
-
-\begin{itemize}
-
-\item \structure{Can you think of some symbols/terms that have different
-    meanings depending on the context?}
-
-\end{itemize}
-
-\end{frame}
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-
-\begin{frame}
-\frametitle{Consistent}
-
-\begin{itemize}
-
-\item Language and terminology must be consistent within the specification
-\item Potential problem with homonyms, for instance consider the symbol $\sigma$
-\begin{itemize}
-\item Represents standard deviation
-\item Represents stress
-\item Represents the Stefan-Boltzmann constant (for radiative heat transfer)
-\end{itemize}
-\item Changing the symbol may be necessary for consistency, but it could adversely effect understandability
-\item Potential problem with synonyms
-\begin{itemize}
-\item Externally funded graduate students, versus eligible graduate students, versus non-VISA students
-%ask who would think about graduate school?
-\item Material behaviour model versus constitutive equation
-\end{itemize}
-\end{itemize}
-
-\end{frame}
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-
-\begin{frame}
-\frametitle{Complete}
-
-\begin{itemize}
-
-\item Internal completeness
-\begin{itemize}
-\item The specification must define any new concept or terminology that it uses
-\begin{itemize}
-\item A glossary is helpful for this purpose
-\end{itemize}
-\end{itemize}
-\item External completeness
-\begin{itemize}
-\item The specification must document all the needed requirements
-\begin{itemize}
-\item Difficulty: when should one stop?
-\end{itemize}
-\end{itemize}
-
-\end{itemize}
-
-\end{frame}
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-
-\begin{frame}
-\frametitle{Incremental}
-
-\begin{itemize}
-
-\item Referring to the specification process
-\begin{itemize}
-\item Start from a sketchy document and progressively add details
-\item A document template can help with this
-\end{itemize}
-\item Referring to the specification document
-\begin{itemize}
-\item Document is structured and can be understood in increments
-\item Again a document template can help with this
-\end{itemize}
-
-\end{itemize}
-
-\end{frame}
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-
-\begin{frame}
-\frametitle{Traceable}
-
-\begin{itemize}
-
-\item Explicit links
-\bi
-\item Within document
-\item Between documents
-\ei
-\item Use labels, cross-references, traceability matricies
-\item Common sense suggests traceability improves maintainability
-\item Shows consequence of change
-\item Minimizes cost of recertification
-\item Additional advantages
-\bi
-\item Program comprehension
-\item Impact analysis
-\item Reuse
-\ei
-\end{itemize}
-
-\end{frame}
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-
 \begin{frame}[allowframebreaks]
 \frametitle{References}