Which of the following number divides (270+370)

#1

Which of the following number divides (270+370)?
how to calculate this?

#2

which q are u refering to
or this is out of quiz question?

EDIT
GOT it ‘^’ were missing wait
i`ll tell u

#3

@be10046.19
u need to have little idea about Fermat`s little theorem

go through these answers
https://www.quora.com/How-do-I-show-that-13-divides-2-70-3-70