联通公司手机话费收费有A套餐（月租费15元，通话费每分钟0.1元）和B套餐（月租费0元，通话费每分钟0.15元）两种．设A套餐每月话费为y₁（元），B套餐每月话费为y₂（元），月通话时间为x分钟．

地理环境与文明起源有密切的关系，孕育古希腊文明的地理环境是（    ）

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    Tom and Tim are brothers. They are 1 Australia. They live in a mountain village. Tom is 104 years old and Tim is 102 years old now. They 2 their story in a book called Enjoy Our Life.

    Here is some of their advice(建议) for living a long, 3 life.

    ★Get up 4. They get up 5 6:30 or 7:00 in the morning.

    ★Have a 6 breakfast. The brothers eat oatmeal(燕麦粥), half a banana,  7 and eggs with a little cheese(奶酪).

    ★8 every day. The brothers like 9 mountains. They also walk on the hills(小山) every day.

    ★Eat a lot of 10, especially(尤其) garlic(大蒜). Garlic is good 11 your health.

    ★Don't eat a lot of salt(盐) and fat. These things are 12 for your body(身体).

    ★Don't listen 13 the doctors always. Most of the doctors don't know what to do with us. When there is 14 wrong with us, they don't know how to treat(治疗) us. They are always surprised(吃惊) to see us live so 15.