This uptempo pop song should be in the key of E flat major according to me.
"Who Can It Be Now?" is a song recorded by Australian band Men at Work. It was released in Australia in 1981, prior to the recording of their 1981 debut album Business as Usual, on which the track was later included.
Funny thing about Colin Hay from Men At Work is he sounds black from the islands of Jamaica, Trinidad, West Indies, Tabago, Bahamas, Caribbean islands and Barbados when he sings.