Yes because it can't be expressed as a fraction
the nummber of sunspots chages in cycles of 11 yaers
The square root of 11 is an irrational number
no because 11 is an odd nummber and 12 is a even and a odd cant go in a even number
No.
No, it is rational.
No.
No.
none
Yes
pi = 3.14159265359
It is composite.