(i) ( a_1 = 3 ), ( d = 7 ), find ( a_{14} )

[ a_n = a_1 + (n-1)d ] [ a_{14} = 3 + (14-1)\cdot 7 = 3 + 13\cdot 7 = 3 + 91 = 94 ]

Answer: ( 94 )

(ii) ( 8, 3, -2, \ldots ), find ( a_{12} )

Common difference ( d = 3 - 8 = -5 )

[ a_{12} = 8 + (12-1)(-5) = 8 + 11\cdot(-5) = 8 - 55 = -47 ]

Answer: ( -47 )