diff --git a/homework4/README.txt b/homework4/README.txt
index 2aab3f6..f5dc95f 100644
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+++ b/homework4/README.txt
@@ -1,80 +1,86 @@
 EXERCISE 4
 Alexis Sáez Uribe 
 Carlo Peruzzo
 
-NOTE(1): Please, make sure of having a folder called "dumps" in the particle code directory to store the results of the simulations
-NOTE(2): We intentionally deactivated the following sections of the CMakeLists.txt because they were not used:
+NOTE(1): In order to run exercise_5.py, you need the solution of the planet system, so you have to first run either the
+main.py or the exercise_6.py with scaling factor equal to 1
+NOTE(2): Please, make sure of having a folder called "dumps" in the particle code directory to store the results of the simulations
+NOTE(3): We intentionally deactivated the following sections of the CMakeLists.txt because they were not used:
 - FFTW
 - Doxygen
 - Google test
 
 ---
 Exercise 1.2:
 The overloaded method createSimulation (three arguments) is taking as an input the functor/function called "createComputes" that has been defined in the file main.py.
 This function is specific for the type of particle that the user has chosen, it sets some physical parameters and
 some methods for the simulation.
 The function createComputes is stored by createSimulation in a object of type std::function<void(Real)> defined in the header <functional>
   "
   Instances of std::function can store, copy, and invoke any Callable target -- functions, lambda expressions,
   bind expressions, or other function objects, as well as pointers to member functions and pointers to data members.
   "
 Coming back to the method createSimulation, after storing "createCompute", it executes
 the method createSimulation (the non overloaded one, with two arguments) which is specific of the daughter class related to the selected type of particle and
 it calls the createComputes stored in the object of type std::function<void(Real)>.
 ----
 
 
 Exercise 2.2:
 For the compute objects type we specified that we want to use shared pointers as object holder, because the structure
 of the particle code involves the use of arrays of shared pointers.
 
 Additional Note: For the case of factory objects, we used the return_value_policy::reference in order to reference an
 existing object and preventing python from taking its ownership.
 
 We use return_value_policy::reference for the factory objects when using the
 Reference an existing object, but do not take ownership. In this way, the C++ side is responsible for managing the
 object’s lifetime and deallocating it when it is no longer used.
 
 ----
 
 
 Exercise 5:
+
+NOTE(1): In order to run exercise_5.py, you need the solution of the planet system, so you have to first run either the
+main.py or the exercise_6.py with scaling factor equal to 1
+
 the solution of exercise 5 is contained in the file exercise_5.py
 in order to run exercise_5.py you need to specify in the order:
 1- the name of the planet
 2- the name of the folder containing the reference solution for the planet (*)
 3- the name of the folder containing the computed solution for the planet (*)
 (*)= or the path of the folder if it is not in the same folder as the script.
 For example the parameters required when launching the python script are:
 mercury Trajectories/ dumps/
 
 The output error will be printed on the screen
 ----
 
 
 Exercise 6
 The solution of exercise 6 is contained in the file exercise_6.py
 in order to run exercise_6.py you need to specify in the order:
 1- number of time steps
 2- time step
 3- name of the planet
 4- scale factor for the velocity
 5- name of the input file containing the initial state of the planet system for the particle code (*)
 (*)= or the path to the file if it is not in the same folder as the script.
 For example the parameters required when launching the python script are:
 365 1 mercury 2.5 init.csv
 The output error will be printed on the screen
 ----
 
 Exercise 7
 The solution of exercise 7 is contained in the file exercise_7.py
 in order to run exercise_7.py you need to specify in the order:
 1- number of time steps
 2- time step
 3- name of the planet
 4- name of the input file containing the initial state of the planet system for the particle code (*)
 (*)= or the path to the file if it is not in the same folder as the script.
 The parameters required when launching the python script are:
 365 1 mercury init.csv
 The output error will be printed on the screen and the plot will be popped up
 ----