Find the unit digit of the following exponential number:

${46}^{31}$

Find the unit digit of the large number:

$4^7$

Find the unit digit of the large numbers:

${64}^{10}$

Find the unit digit of the large numbers:

$9^{12}$

Find the unit digit of the large number:

Find the degree of the following expression.

$x^5$

Find the degree of the following expression.

$-3p^3{q}^2$

Find the degree of the following expressions.

$-4x{y}^2{z}^3$

Find the degree of the following expressions.

$12xyz-3x^3{y}^{2}z+z^8$