Find the acute angle between the intersecting lines

xequals$=7$ t$7$t$,$

yequals$=6$ t$6$t$,$

zequals$=$negative $3$ t$3$t

and

xequals$=11$ minus $3$ t$113$t$,$

yequals$=19$ plus $7$ t$19+7$t$,$

zequals$=6$ t$6$t$.$

Question content area bottom

Part $1$

The angle is

enter your response here

radians.

$($Round to the nearest thousandth as$$ needed.$)$