问题 选择题
下列方程组是二元一次方程组的有(  )个.
(1)
2m-n=1
m+n=2
(2)
x-2y=3
y+z=1
(3)
x=1
x+2y=5
(4)
x2+y=5
x-y=4
A.1个B.2个C.3个D.4个
答案

根据二元一次方程组的定义,可知(1)(2)为二元一次方程组;

∵x=1和x2+y=5不是二元一次方程,

∴(3)(4)不是二元一次方程组.

∴二元一次方程组为3个.

故选B.

问答题

2010年1月1日,甲公司支付价款1000万元(含交易费用)从上海证券交易所购入A公司同日发行的5年期公司债券12500份,债券票面价值总额为1250万元,票面年利率为4.72%,于年末支付本年利息(即每年利息为59万元),本金在债券到期时一次性偿还。已知该债券的实际利率为10%,甲公司没有意图将该债券持有至到期,划分为可供出售金融资产。其他资料如下:
(1)2010年12月31日,A公司债券的公允价值为90万元(不含利息),A公司仍可支付债券当年的利息。
(2)2011年,由于产品缺乏竞争力、内部管理松懈,A公司财务状况恶化,但仍可支付债券当年的利息;2011年12月31日,A公司债券的公允价值为750万元(不含利息)。甲公司预计如果A公司不采取有效措施,该债券的公允价值会持续下跌。
(3)2012年12月31日,A公司债券的公允价值下跌为700万元(不含利息),A公司仍可支付债券当年的利息。
(4)2013年,A公司通过加强管理、技术创新和产品结构调整,财务状况有了显著改善,2013年12月31日,A公司债券的公允价值上升为1200万元(不含利息),A公司仍可支付债券当年的利息。
(5)2014年1月20日,通过上海证券交易所出售了A公司债券12500份,取得价款1260万元。
要求:
(1)编制2010年1月1日甲公司购入该债券的会计分录。
(2)计算2010年12月31日甲公司该债券投资收益、应计利息和利息调整摊销额,并编制相应的会计分录。
(3)计算2011年12月31日甲公司该债券投资收益、应计利息和利息调整摊销额,并编制相应的会计分录。
(4)计算2012年12月31日甲公司该债券投资收益、应计利息和利息调整摊销额,并编制相应的会计分录。
(5)计算2013年12月31日甲公司该债券投资收益、应计利息和利息调整摊销额,并编制相应的会计分录。
(6)计算2014年1月1日甲公司售出该债券的损益,并编制相应的会计分录。
(答案中的金额单位用万元表示)

阅读理解

阅读短文,选择正确答案。

      Water is all around us. Water is in the ocean. Water is in the lakes and rivers. Water is in the air. There is

more water than land on the earth. All things must have water to live. The plants must have it. The animals must

have it. We must have it, too. We cannot live without drinking water. Sometimes, we do not have all the water

that we need. The land will dry up without water. Sometimes, there can be too much water in the land. If it rains

very, very hard, the rain water will run down the hills. It takes some of the land with it when it runs down the

hills. It is called erosion when the water takes the land away. 

      Water on the earth will never be used up. It goes from the ocean to the air to make clouds. Then, it falls

from the clouds down to the land. It runs off the land and out to the ocean again. The clouds make rain. The rain

falls onto the land. Some of it goes into the ground. Some of it washes down and goes back into the ocean.

Some water that falls down from the clouds is not rain. Some of it washes down and goes back into the ocean.

Some water that falls down from the clouds is not rain. Some of this water is snow. The snow is made of

water. Some water that is not rain or snow falls down from the clouds. Some of this water is sleet (雨夹雪).

The sleet is made of little pieces of ice. Some water that is not rain or snow or sleet falls down from the clouds.

Some of this water is hail (冰雹). The hail is made of ice balls!

1.According to the passage, we know that ________. [ ]

A.We can live without water

B.the animals don't need water

C.Human beings can't live without water

D.only plants must have water

2.Which of the following is not made of water? [ ]

A.Snow

B.Sleet

C.Hail

D.Land

3."Erosion" in the passage means ________. [ ]

A.地震

B.雪崩

C.侵蚀

D.霜冻

4.Which of the following shows the water cycle (循环)? [ ]

A.Water from the ocean→air→clouds→ rain→land→ocean

B.Water in the air→clouds→rain→land→hail

C.Water in the clouds→snow→land→ocean

D.Rain→land→river→ocean→storm