Thank you! Here's what i did:

let a_i=student that is equal to the other students in the row's sum

then a1+a2+...+an=98*99/2-(a1+a2+...+an)

moving the a1+a2+...+an to the other side and dividing by two yeilds

a1+a2+...+an=98*99/4≠integer, so contradiction and hence not possible.

Thanks,

Tina Jin