Update lab1_student_instructions_serializable.md

removed "experimental"

Author: glennfawcett

Diff for: lab1_student_instructions_serializable.md

@@ -161,7 +161,7 @@ COMMIT;
 
 -- select_follower_read (implicit)
 --
-SELECT * FROM alerts  as of system time experimental_follower_read_timestamp()
+SELECT * FROM alerts  as of system time follower_read_timestamp()
 WHERE customer_id=9743;
 
 -- select_normal_different_id
@@ -416,4 +416,4 @@ WHERE customer_id=9743;
 * What are the differences in response times between SFU and noSFU?
 
 #### Q11
-* Why is the overall throughput so much better?
+* Why is the overall throughput so much better?