diff --git a/exercises/exercise-mainfile/properties.hh b/exercises/exercise-mainfile/properties.hh
index ce835d308f37dad995e6ca7956896d47c037f399..309a066e30fdca6f2961942583263003ec0853ad 100644
--- a/exercises/exercise-mainfile/properties.hh
+++ b/exercises/exercise-mainfile/properties.hh
@@ -35,7 +35,6 @@
 #include <dumux/discretization/ccmpfa.hh>
 #include <dumux/discretization/box.hh>
 
-
 #include <dumux/porousmediumflow/1p/model.hh>
 // TODO: dumux-course-task 3
 // uncomment the incompressiblelocalresidual which is a specialization of the standard immiscible localresidual for one phase incompressible cases and provides an analytic jacobian.
diff --git a/exercises/solution/exercise-mainfile/1pproblem.hh b/exercises/solution/exercise-mainfile/1pproblem.hh
index c59565097b35efb053895b9a96f2747963c3650b..8f1ec58929232756025e5d14f8daffc7ae9cb8d8 100644
--- a/exercises/solution/exercise-mainfile/1pproblem.hh
+++ b/exercises/solution/exercise-mainfile/1pproblem.hh
@@ -24,9 +24,9 @@
 #ifndef DUMUX_EX_MAINFILE_ONEP_TEST_PROBLEM_HH
 #define DUMUX_EX_MAINFILE_ONEP_TEST_PROBLEM_HH
 
-#include <dumux/porousmediumflow/problem.hh>
 #include <dumux/common/properties.hh>
 #include <dumux/common/boundarytypes.hh>
+#include <dumux/porousmediumflow/problem.hh>
 
 namespace Dumux {
 
@@ -55,7 +55,7 @@ public:
     OnePTestProblem(std::shared_ptr<const GridGeometry> gridGeometry)
     : ParentType(gridGeometry)
     {
-        FluidSystem::Component::init(/*tempMin=*/272.15,
+        FluidSystem::Component::init(/*tempMin=*/273.15,
                                      /*tempMax=*/294.15,
                                      /*numTemp=*/10,
                                      /*pMin=*/1.0e4,
@@ -104,6 +104,7 @@ public:
     {
         return PrimaryVariables(1.0e5);
     }
+
 };
 
 } // end namespace Dumux
diff --git a/exercises/solution/exercise-mainfile/CMakeLists.txt b/exercises/solution/exercise-mainfile/CMakeLists.txt
index fe4b84747f2b0c41e5e6177b08bf3ebb8fa932e1..ace271dd31b259da48c142b2e798b1545e7a307c 100644
--- a/exercises/solution/exercise-mainfile/CMakeLists.txt
+++ b/exercises/solution/exercise-mainfile/CMakeLists.txt
@@ -3,7 +3,5 @@ dumux_add_test(NAME exercise_mainfile_a_solution
                SOURCES exercise1pa_solution_main.cc
                COMPILE_DEFINITIONS TYPETAG=OnePIncompressible)
 
-# here, add the two-phase non-isothermal simulation program
-
 # add a symlink for each input file
-add_input_file_links()
+add_input_file_links()
\ No newline at end of file
diff --git a/exercises/solution/exercise-mainfile/exercise1pa_solution_main.cc b/exercises/solution/exercise-mainfile/exercise1pa_solution_main.cc
index 22d8495b519bb647aa03d5f5242578c77941c7fd..c25d369209e2aa93b6ad49af4495f1e034f51fa6 100644
--- a/exercises/solution/exercise-mainfile/exercise1pa_solution_main.cc
+++ b/exercises/solution/exercise-mainfile/exercise1pa_solution_main.cc
@@ -23,7 +23,6 @@
  */
 #include <config.h>
 
-#include "1pproblem.hh"
 #include "properties.hh"
 
 #include <iostream>
@@ -100,8 +99,8 @@ int main(int argc, char** argv)
 
     Dune::Timer timer;
 
-    // TODO: dumux-course-task
-    // change the differentiation method to analytic by changing from DiffMethod::numeric to DiffMethod::analytic
+    // TODO: dumux-course-task 3
+    // Change the differentiation method to analytic by changing from DiffMethod::numeric to DiffMethod::analytic
 
     // the assembler for stationary problems
     using Assembler = FVAssembler<TypeTag, DiffMethod::analytic>;
diff --git a/exercises/solution/exercise-mainfile/exercise_mainfile_a_solution.input b/exercises/solution/exercise-mainfile/exercise_mainfile_a_solution.input
index f3d01fc5abac4e26e944289f7dd973b7d4c922d8..c9eb9c076df76a47da255df6927046b771bb2088 100644
--- a/exercises/solution/exercise-mainfile/exercise_mainfile_a_solution.input
+++ b/exercises/solution/exercise-mainfile/exercise_mainfile_a_solution.input
@@ -15,3 +15,4 @@ PermeabilityLens = 1e-12 # [m^2]
 
 [Assembly.NumericDifference]
 PriVarMagnitude = 1e5
+BaseEpsilon = 1e-10
\ No newline at end of file
diff --git a/exercises/solution/exercise-mainfile/properties.hh b/exercises/solution/exercise-mainfile/properties.hh
index e6f9e93cc7966dc5209c2934248c51dbf24692be..ee94cf20eddeb736f98a6086c42bd8e858371e95 100644
--- a/exercises/solution/exercise-mainfile/properties.hh
+++ b/exercises/solution/exercise-mainfile/properties.hh
@@ -36,7 +36,7 @@
 #include <dumux/discretization/box.hh>
 
 #include <dumux/porousmediumflow/1p/model.hh>
-// TODO: dumux-course-task
+// TODO: dumux-course-task 3
 // uncomment the incompressiblelocalresidual which is a specialization of the standard immisible localresidual for one phase incompressible cases and provides an analytic jacobian.
 #include <dumux/porousmediumflow/1p/incompressiblelocalresidual.hh>
 
@@ -45,9 +45,9 @@
 
 namespace Dumux::Properties {
 
-// Create the new type tag nodes.
+// Create the new type tag nodes:
 // Here we define the incompressible type tag as well as the compressible type tag.
-// The incompressible uses a different fluidsystem than the compressible.
+// The incompressible uses a different fluidsystem than the compressible
 namespace TTag {
 struct OnePBase { using InheritsFrom = std::tuple<OneP>; };
 struct OnePIncompressible { using InheritsFrom = std::tuple<OnePBase, CCTpfaModel>; };
@@ -78,7 +78,7 @@ public:
     using type = FluidSystems::OnePLiquid<Scalar, Components::SimpleH2O<Scalar> >;
 };
 
-// TODO: dumux-course-task
+// TODO: dumux-course-task 3
 // set the OneP Incompressible local residual for the OnePIncompressible type tag. This provides an analytic jacobian to be used for the analytic solution. Change that by setting:
 template<class TypeTag>
 struct LocalResidual<TypeTag, TTag::OnePIncompressible> { using type = OnePIncompressibleLocalResidual<TypeTag>; };