Evaluate: sqrt(15u^6y^4)sqrt(5u^7y^3)

Expression: $\sqrt{ 15{u}^{6}{y}^{4} }\sqrt{ 5{u}^{7}{y}^{3} }$

$\sqrt{ 15{u}^{6}{y}^{4} \times 5{u}^{7}{y}^{3} }$

$\sqrt{ 75{u}^{13}{y}^{7} }$

$5{u}^{6}{y}^{3}\sqrt{ 3uy }$