how's that?

Từ điển Oxford Advanced Learner 8th

ˌhow's ˈthat? idiom
(informal)
1. used to ask the reason for sth
• ‘I left work early today.’ ‘How's that (= Why)?’
2. used when asking sb's opinion of sth
• I'll tuck your sheets in for you. How's that? Comfortable?
•Two o'clock on the dot! How's that for punctuality!
Main entry: ↑how_idiom