设等比数列$\left\{a_n\right\}$的公比为q，前n项和为$S_n$，若$S_{n+1},S_n,S_{n+2}$成等差数列，则公比q为（  ）

    Guided Walking Week April 2016

    Dates: April 30^th-May 7^th 2016

    Location: Abdet, Costa Blanca

    A week of guided walking in the mountains around Abdet. Highlights include the climbing of Valencia's highest summit (Sierra de Aitana), traveling completely around the impressive Puig Campana, and several explorations in the Sierra de Aitana. Ancient trails lead through spectacular canyons(峡谷) to abandoned settlements situated high in the mountains. You will discover the snow trader routes which lead from the incredible snow holes high in the mountains down to the villages and towns on the coast. These years, golden eagles have made a return to this area, and you may also see other animals—wild goats, foxes, wild pigs and red squirrels.

    As part of the week you are invited to help clear some local walking paths. This involves clearing collapsed （坍塌的） walls and rocks, cutting back fallen trees. This is of course optional and is just for half a day, it's actually great fun!

Price:$499

Includes:

    Accommodation in the beautiful mountain village of Abdet

    All food-good home cooking

    Beer, wine, soft drinks

    Snacks and post walk treats

    Packed lunches & drinks(except café/bar visits)

    Expert guiding

    Photos/Videos of your days in the mountains

    Airport pick-up/return $25 each way(fly to Alicante)

    Single room supplement $75

    To book or get further information, please contact info@abdet.com.

党的十八大从国家、社会、公民三个层面概括社会主义核心价值观的价值目标、价值取向和价值准则，倡导富强、民主、文明、和谐；自由、平等、共整个、法治；爱国、敬业、诚信、友善。社会主义核心价值观是人生奋斗的梦想之舵，是中华民族的精神之钙，是当代中国的兴国之魂。

某校决定围绕“爱国、敬业、诚信、友善”等内容，对学生开展社会主义核心价值观宣传教育活动，请你参与并完成下列任务。