$(3)$ What is the angle between the planes $4x-9y-z=2$ and $x+2y-14z=-6.$

$(4)$ Find the derivative, the unit tangent vector, and the equation of the tangent line if $t=1$ if vec$(r)(t)=(t^3-1,e^{2t},cos(t))$

$(5)$ Find the unit normal and the binormal vectors if vec$(r)=(cos(2t),sin(2t),3).$

$(6)$ Find the arc length for vec$(r)(t)=(3-4t,6t,9+2t)$ for $-6t8$

Can you Please solve questions $3$ and $4$