Hello everybody

I have a question concerning
Exercise 2.
I'm sorry i tried to find an answer before posting but couldn't myself.
So here is my question... it is about the
2nd and the 3rd barre and especially about the following sequences :
2nd barre : 1 + 2 +
3rd barre : 2 + 3 +
in the writting, both used quaver notes... until here it's ok for me...
but the 2nd barre ( + 2 ) uses a quaver link whereas the 3rd barre ( + 3 ) does not... and i can't here the difference in the sound sequence... am i missing something ?
thank you