Section 10.7: Problem 1 (1 point) Find the domain of the vector functions, r(t), listed below. You may use "-INF" for - and use "INF" for as necessary, and use "U" for a union symbol if a union of intervals is needed. a) r(t) = (ln(5t), t + 20, (0,18) b) r(t) = (t-2, sin(6t), t) t c) r(t) = (e-2, 36 1/3) 19-t