In an AP: (i) given a = 5, d = 3, a_n = 50, find n and S_n. (ii) given a = 7, a_3 = 35, find d and S_{13}. (iii) given a_{12} = 37, d = 3, find a and S_{12}. (iv) given a_4 = 15, S_9 = 125, find d and a_{10}. (v) given d = 5, S_5 = 75, find a and a_9. (vi) given a = 2, d = 8, S_6 = 90, find n and a_n. (vii) given a = 8, a_n = 62, S_n = 210, find n and d. (viii) given a = 4, d = 2, S_n = -14, find n and a. (ix) given a = 3, n = 8, S = 192, find d. (x) given l = 28, S = 144, and there are total 9 terms. Find a.