方程组6x-y-z=20x2+y2+z2=1979的所有正整数解是______.

题型:填空题

问题:

方程组
6x-y-z=20
x2+y2+z2=1979
的所有正整数解是______.
考点:三元(及三元以上)一次方程(组)的解法
题型:填空题

下列词语中加点的字,每对的读音完全相同的一组是

A.信/包育/追折/火积薪

B.计/市/旱意/而不舍

C.好/围/头/空来风

D.护/奴怒/目而视

题型:填空题

某市修建一条快速干线,初步拟定两条备选路线,即沿河路线与穿山路线,两条路线的平均车速都提高了50km/h,日平均流量都是6 000辆,寿命均为30年,且无残值,基准收益率为12%,其他数据如表3-2所示。




已知(P/F,12%,10)=0.322 0,(P/F,12%,20)=0.103 7,(A/P,12%,30)=0.124 1。
问题:1. 试用生命周期费用理论分析两条路线的优劣,并做出方案选择(计算结果保留两位小数)。

题型:填空题

When your pet meets your infant(婴儿),it might not be love at first sniff. When Jennifer brought her baby home from the hospital, her cherished dogs had very different reactions. Her Boxer, Sonya, was immediately gentle and protective. But Tiger, the Pomeranian, was less welcoming. “If any diapers(尿布)or toys were on the floor, he peed on them,” says the Greenbrier, mom. In the eyes of a pet, there’s a new star in home who’s stealing his spotlight. Even the gentlest animal will probably act up if he doesn’t get his usual attention. These simple steps will help your pet adjust and keep your baby safe.

Introduce Them with Care

Your newborn and per’s first encounter can set the tone for their relationship. To make it as smooth as possible, try this trick from Caryn Ruiz:“Before we left the hospital, my husband took blankets home to our dog, Daisy, so she’d know our newborn Devon’s smell.” When you get home, have your husband carry the baby so you can greet your pet without worrying about her jumping on you. A cat will likely walk away at first, while a dog probably wants to investigate right away.

To introduce your baby, get down on your pet’s level and let her have a hello sniff. Don’t panic and pull your baby away unless your pet is barking or hissing, because it’ll send the message that the baby is a threat.

Learn the Safety Basics

No matter how smoothly the introduction goes, there are certain safety rules you should follow. Never leave your baby alone with the pet. Even the gentlest animal can react unpredictably. Your baby’s crying could frighten your cat, or your dog could suddenly become territorial. Consider setting up baby gates to limit your pet’s access. To keep your cat from jumping into the bassinet(有篷盖的摇篮), try putting mosquito netting over the top. Cats hate sticky paws, so keep the crib(有栏杆的婴儿床)and changing table off-limits by lining the edges with sticky strips made for furniture. You can also train your dog to sleep in a crate(大木箱).

小题1:At the beginning of the passage, the author uses the stories to_____.

A.illustrate possible reactions when pets meet a newborn baby

B.show that pets don’t like a newborn baby

C.prove how friendly a pet is when it meets a newborn baby

D.introduce how terrible the pets are when a mother gets a baby home小题2:Who is Sonya mentioned in the 1 st paragraph?

A.Jennifer’s dog.

B.Jennifer’s baby.

C.Jennifer’s husband.

D.A pet expert.小题3:What can we infer from the passage?

A.Cats are more welcoming than dogs when they meet a newborn baby.

B.You must show your baby to your pet dog when it is barking.

C.You should never keep a baby together with your pet.

D.The first introduction of your newborn baby to your pet is important.小题4: According to the passage, to keep your baby safe, you should do the following things EXCEPT_____.

A.introducing your baby to your pet with care

B.leaving your baby alone with your pet at the first day when they meet

C.setting up baby gates to limit your baby

D.keeping your pet away from your baby

题型:填空题

按《道路运输条例》的规定,取得一类汽车维修业务许可的企业,可以按托修方要求,更换发动机总成,无需查看相关手续。

题型:填空题

建筑立面图不能用()进行命名

A、建筑位置

B、建筑朝向

C、建筑外貌特征

D、建筑首尾定位轴线

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