Complete question 4 and 5

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diff --git a/assignments/3/README.md b/assignments/3/README.md
index 0590027..7f27687 100644
--- a/assignments/3/README.md
+++ b/assignments/3/README.md
@@ -104,6 +104,18 @@ The UBS broker company has a database server with three disks.
 Both the accounting and stock exchange applications share the same disk, and they are experiencing performance problems.
 Discuss potential reasons for the performance problem, and suggest how to reduce I/O contention.
 
+If the database server has three separate disks serving two different applications then it might make sense to allocate a separate disk for each application.
+At the moment the database server is performing all I/O operations a single disk which will bottleneck all read/writes from each application because
+hdd disk needs to seek back and forth to the appropriate portions on the disk to read/write the necessary data. 
+
+If the applications are read heavy applications then it would make sense to ensure that solid state drives are used to optimize the reads.
+Splitting the database files across disks will also allow for better parallelization of responding to read/write requests.
+If possible it might be worth dedicating one disk as a primary that will serve only writes and replicate the primary to the other two disks to utilize them
+specifically for reads.
+
+Other areas to look at is the query logs to see if there are expensive queries due to many disk seeks on disk to respond with all the data.
+In this case it might make sense to add missing indexes to try to make sure as much of the related data is logically grouped on disk to reduce disk seeks back and forth.
+
 ## Question 5
 
 Consider the concurrent execution of the following transactions.
@@ -118,6 +130,9 @@ Consider the concurrent execution of the following transactions.
 
 **List two problems that may occur from the concurrent execution of these two transactions.**
 
+1. T1/T2 will overwrite data `A` depending on the order the transactions are committed.
+2. T2 could be operating on a stale read of data `C` that is being modified in T1.
+
 ## Question 6
 
 The Edmonton International Airport would like to implement a database that will be used to keep track of airplanes, their owners, airport employees, and pilots.