Improve 1984/mullender alt code

Now you can specify the number of microseconds to sleep in between
writes! This makes it easier to experiment with different speeds as well
as solve any problems if your CPU is too slow or too fast

BTW: is there such a thing as too fast a CPU ? :-) actually yes for
certain code which is probably not as uncommon as you think :-) ).

faq.md

@@ -41,9 +41,13 @@ can enjoy this entry. Try:
 
 ```sh
 make alt
-./mullender.alt
+./mullender.alt [microseconds]
 ```
 
+The microseconds defaults to 10000.
+
+Thank you Cody!
+
 See also [Yusuke Endoh](/winners.html#Yusuke_Endoh)'s entry
 [2015/endoh3](/2015/endoh3/README.md) entry which lets one compile it and run
 it.
@@ -353,15 +357,24 @@ try the alternative code added by [Cody Boone Ferguson](/winners.html#Cody_Boone
 
 ```sh
 make alt
-./mullender.alt
+./mullender.alt [microseconds]
 ```
 
+where microseconds is the number of microseconds to sleep between writes.
+Default 10000. This is useful to see different speeds as well as if your CPU is
+too slow or too fast for the entry. See the
+[README.md](/1984/mullender/README.md) for more details.
+
 Thank you Cody for your help!
 
-BTW: in this case it's a slight adjustment to our original suggested code:
+BTW: in this case it's a slight fix and improvement to our original suggested
+code:
 
 	main(){int i=512;do write(1,"  :-)\b\b\b\b",9),usleep(i);while(--i);}
 
+BTW: is there such a thing as too fast a CPU ? :-) actually yes for certain code
+which is probably not as uncommon as you think :-) ).
+
 break;
 
 - case [1991/davidguy](years.html#1991_davidguy): disable access