$$ \begin{cases} \Delta \vec r_{0\rarr1}&=(5.70\ut{m})\j\\ \Delta r_{1\rarr2}&=3.40\ut{m}\\ \theta_{1\rarr2}&=-\cfrac{\pi}{4}\ut{rad}\\ \Delta r_{2\rarr3}&=0.91\ut{m}\\ \theta_{2\rarr3}&=-\cfrac{3\pi}{4}\ut{rad}\\ \end{cases} $$ $$ \begin{aligned} \Delta \vec r_{1\rarr2}&=r_{1\rarr2}\cos\theta_{1\rarr2}\i+r_{1\rarr2}\sin\theta_{1\rarr2}\\ &=3.40\cos\(-\cfrac{\pi}{4}\)\i+3.40\sin\(-\cfrac{\pi}{4}..