题目内容：

Mariah Nablo is a sixteenyearold girl.When she was six，she watched a TV show.It talked about problems faced by mountain gorillas(山地大猩猩) in Africa.She learned that they were endangered because their living space was losing.The cause of this trouble was people illegally mining(非法采矿) for Coltan，a material used to make mobile phones.Mariah was so shocked by what she learned that she wanted to do something about it.But what?

Her inspiration came when she was visiting the Buffalo Zoo in Buffalo，New York.She saw a collection box with a sign that said，“Answer the call of the wild.Recycle mobile phones and help save gorillas.”This is when she learned about an organization called EcoCell.Through EcoCell，she realized that one way she could help protect gorillas was to collect mobile phones for recycling.This not only keeps mobile phones out of landfills(废物填埋地)，but helps cut down on the need for Coltan and illegal mining.So，at age 6，Mariah started to work with EcoCell.With the help of her parents，she also started her own project—Mariah Saves Gorillas.

Mariah's project，for the past 10 years，has collected thousands of mobile phones and kept ewaste out of landfills.And，recently，Mariah has been spending her time educating people about how recycling can save gorillas.

1.How did Mariah learn about the problem faced by mountain gorillas in Africa？(不超过5个词)

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2.What can Coltan be used for？(不超过10个词)

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3.What has Mariah been doing recently？(不超过15个词)

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