In an AP:
(i) Given a=5, d=3, `a_(n) = 50`, find n and `S_(n)`
(ii) given a=7, `a_(13) = 35`, find d and `S_(13)`.
(iii) given `a_(12) = 37, d=3`, find a and `S_(12)`
(iv) given `a_(3) = 15, S_(10) = 125`, find d and `a_(10)`
(v) given a=2, d= 8, `S_(n) = 90`, find n and `a_(n)`
(vi) given `a_(n) = 4, d=2, S_(n) = - 14`, find n and a.
(vii) given l=28, S= 144, and there are total 9 terms, find a.