Write the degree of each of the following polynomials :
$(i)$ $5 x^{3}+4 x^{2}+7 x$
$(ii)$ $4-y^{2}$
Find the zero of the polynomial : $p(x)=a x,\,\, a \neq 0$
Find the following products using appropriate identities :
$(i) $ $ (x + 3) (x + 3)$
$(ii)$ $(x -3) (x + 5)$
Without actually calculating the cubes, find the value of each of the following : $(28)^{3}+(-15)^{3}+(-13)^{3}$
Expand each of the following, using suitable identities : $(x+2 y+4 z)^{2}$