正项等差数列\(\{a _{n} \}\)中，已知\(a _{1} +a _{2} +a _{3} =15\)，且\(a _{1} +2\)，\(a _{2} +5\)，\(a _{3} +13\)构成等比数列\(\{b _{n} \}\)的前三项．
\((\)Ⅰ\()\)求数列\(\{a _{n} \}\)，\(\{b _{n} \}\)的通项公式；
\((\)Ⅱ\()\)求数列\(\{a _{n} \boldsymbol{⋅}b _{n} \}\)的前\(n\)项和\(T _{n}\)．