Consistent instructions and examples

I started off with "hints" that required the poor student to piece
together the information from incomplete bits. A complete example is
like a picture that is worth 1000 words and far clearer.

05_arrays2.zig

@@ -2,12 +2,14 @@
 // Zig has some fun array operators.
 //
 // You can use '++' to concatenate two arrays:
+//
 //   const a = [_]u8{ 1,2 };
 //   const b = [_]u8{ 3,4 };
-//   const c = a ++ b ++ [_]u8{ 5 }; // 1,2,3,4,5
+//   const c = a ++ b ++ [_]u8{ 5 }; // equals 1 2 3 4 5
 //
 // You can use '**' to repeat an array:
-//   const d = [_]u8{ 1,2,3 } ** 2; // 1,2,3,1,2,3
+//
+//   const d = [_]u8{ 1,2,3 } ** 2; // equals 1 2 3 1 2 3
 //
 const std = @import("std");
 
@@ -15,15 +17,20 @@ pub fn main() void {
     const le = [_]u8{ 1, 3 };
     const et = [_]u8{ 3, 7 };
 
-    // I want this to contain digits: 1 3 3 7
+    // (Problem 1)
+    // Please set this array concatenating the two arrays above.
+    // It should result in: 1 3 3 7
     const leet = ???;
 
-    // I want this to contain digits: 1 0 0 1 1 0 0 1 1 0 0 1
+    // (Problem 2)
+    // Please set this array to using repetition.
+    // It should result in: 1 0 0 1 1 0 0 1 1 0 0 1
     const bit_pattern = [_]u8{ ??? } ** 3;
 
-
+    // Okay, that's all of the problems. Let's see the results.
+    //
     // We could print these arrays with leet[0], leet[1],...but let's
-    // have a little preview of Zig 'for' loops instead!
+    // have a little preview of Zig "for" loops instead:
     std.debug.print("LEET: ", .{});
 
     for (leet) |*n| {