Fragen 1-3 für Kategorie Rechnen Level 4

src/main.c

@@ -520,13 +520,28 @@ Level rechnenlevel3 =
         .size = 12
     };
 
+
+    Question rechnenQst37= {.question = "8 - 3", .answer = "5"};
+    Question rechnenQst38= {.question = "20 - 11", .answer = "9"};
+    Question rechnenQst39= {.question = "15 - 7", .answer = "8"};
+
+    Level rechnenlevel4 = 
+    {
+        .questions = 
+        {
+             rechnenQst37, rechnenQst38, rechnenQst39, 
+        },
+        .size = 3
+    };
+
+
     Category rechnen = 
     {
-        .size = 3, // size = Anzahl Level
+        .size = 4, // size = Anzahl Level
         .name = "Kopfrechnen", 
         .lvlQuestions = 
         {
-           rechnenlevel1, rechnenlevel2, rechnenlevel3,
+           rechnenlevel1, rechnenlevel2, rechnenlevel3, rechnenlevel4,
         }
     };