A $350-$m$-$ radius ci rcular curve will be used to connect two

tangents intersect ing at $72\backslash$deg $.$ I t is desi red to provide a spi ral curve

for smooth t ransi t ion between the tangent and the ci rcular curve.

I f the center of the curve is moved back at $1\mathrm{.}2$ m$,$ determine the

length of the spi ral.