Which of layers of earth has the following three characteristics

Is δ pmr similar to δ smn ? if so, which postulate or theorem proves these two triangles are similar?

Find the value of x that will make l ll m

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