single or plural?

[reach]

Are these below single nouns or plural nouns?

One and a half days (is or are)
one day and a half (is or are)
one day and a half day (is or are)

A half and a hahf (is or are)
A half and one third (is or are)
a half and two third (is or are)

one point one (is or are).

I am looking forward to your reply. thank you.

[Alan]

Anything greater than one is plural, thus one-and-a-half days (etc.) ARE...