Multiply and simplify completely: $\sqrt[\phantom{2}]{10x^{11}{y}^{18}}*\sqrt[\phantom{2}]{2x^{10}{y}^{-8}}$

Your answer will be in the form $A\sqrt[\phantom{2}]{B},$ where A and $B$ are expressions. Enter your expressions for A and $B$ in the boxes below.

$A=$

$B=$