Given: r(t) = i + 6j + arctan (t) k 1. Find the domain. 2. lim r(t) = t-00 3. Given: 7(t) = 2t57 + In(t) j + e3tk, r' (t) = 4. Where is r(t) = (t2 - 4t)i+ ( -2t) j+8k smooth? Explain your answer. 5. Find the anti-derivative r(t) for the differential equation r '(t) = ti + cos (2t)] + 3t2k that satisfies the initial condition r(0) = i + 3j + 2k