(10 points) Consider the parametric curve given by = t+ In(t), y = 7t - 7 In(t) (a) Find dy/dax and day/ dax in terms of t. dy/dr = day/ dx2 = (b) Using "less than" and "greater than" notation, list the t-interval where the curve is concave upward. Use upper-case "INF" for positive infinity and upper-case "NINE" for negative infinity. If the curve is never concave upward, type an upper-case "N" in the answer field. t-interval