diff --git a/education/software development/ECE1400/Chapter 4 Exercises.md b/education/software development/ECE1400/Chapter 4 Exercises.md
index 8090369..fb57aaa 100644
--- a/education/software development/ECE1400/Chapter 4 Exercises.md	
+++ b/education/software development/ECE1400/Chapter 4 Exercises.md	
@@ -10,7 +10,8 @@ c. `-1`, `-1`
 d. `1`, `2`
 # 9.
 a. `63 8`
-b. ``
-
+b. `1 2 3`
+c. `0 1 3`
+d. 
 # 11.
 # 15.