Can someone explain this to me. i don't understand it.

What is the value with a place of tenths in 907.456 1) 0 2) 6 3) 4 4) 5

Plz determine whether the polynomial is a difference of squares and if it is, factor it. y2 – 196 is a difference of squares: (y + 14)2 is a difference of squares: (y – 14)2 is a difference of squares: (y + 14)(y – 14) is not a difference of squares

Ineed to know the answer to this algebra question.