题干

日本福岛第一核电站事故释放出的人工放射性核素碘-131(I)一旦被人体吸入,可能会引发甲状腺疾病。下列说法正确的是

A:I是一种新元素

B:I的摩尔质量为131g

C:I核内有78个中子

D:碘元素位于周期表第四周期

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C

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    Guided Walking Week April 2018

    Date: April 30th—May 7th 2018

    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 walls and rocks, cutting back fallen trees. This is of course optional and is just for half a day, and 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@abdct.com.