Can I file for new H1B from outside of US while waiting for I140 approval?


I am currently on H1B visa and My max out date is 04-Sep-2017. My PERM was approved last October 2016 and My company filed for I-140 this year during early March. While I am waiting for the I140 approval, there is some family emergency that I need to travel India and I am not sure if I can enter into USA before My max out date 04-Sep-2017.

If in case I am unable to enter into USA before My max out period and I-140 is also not approved by then,

a) Can I request My employer to initiate a new H1B visa??
b) If My employer agrees to raise H1B visa, will it go under lottery CAP?
c) Is there any rule that My I140 will be invalid if I go out of USA?

Please help me to get all these clarified. Thank you!!!