No, though if it's not there it's usually implied.2."On Sunday, millions of people in Africa's largest country begin voting on whether to split it in two."
I'm confused because I've thought that 'whether' should be always followed by 'or not', or 'or' in the sentence.It depends whether (or not) they want to make the implicit explicit.In
thesentence 2, I think the sentence means the as same as "On Sunday,..... whether to split in two or not."
esnative speakers usually omit "or not" after "whether"?