There aren't many answers to the good questions you asked. Just by trial and error, I have found that the range -1E99:1E99 works pretty well as a catch-all for wrong answers.
Lesson
Numerical Question in Lesson Module
ဆွေးနွေးပွဲ သော့ခတ်ထားသောကြောင့် အကြောင်းပြန်၍ မရတော့ပါ။