Bungee jumping is an activity about jumping from a tall structure while connected to a large elastic cord(有弹性的绳子). The tall structure is usually a fixed object, such as a building, bridge or crane; but it is also possible to jump from a movable object, such as a hot-air balloon or helicopter, that has the ability to stay over one place on the ground; fixed-wing aircraft are unsuitable because they only stay high when moving quickly forward.

When the person jumps, the cord stretches to absorb (吸收)the energy of the fall, then the jumper flies upwards again as the cord jumps back. The jumper oscillates(摆动)up and down until all the energy is used up.

The word bungee first appeared around 1930 and was the name for a rubber eraser. The first modern bungee jumps were made on 1 April 1979 from the 250-foot Clifton Suspension Bridge in Bristol, by David Kirk, Chris Baker and Alan Weston of the Dangerous Sports Club. The jumpers continued with jumps in the US from the Golden Gate and Royal Gorge bridges, spreading the concept worldwide. By 1982 they were jumping from mobile cranes and hot-air balloons. Later they put on commercial(商业的)shows, which began in 1986.

As with any sport, injuries can still happen, and there have been deaths. A relatively common mistake in the cases that may cause death is to use a cord that is too long. The cord should be fully shorter than the height of the jumping place to allow it room to jumper either starts to slow down or keeps speeding up depending upon the speed of falling.

小题1:Which of the following is NOT suitable for bungee jumping?

A．The fixed-wing aircraft

B．The helicopter

C．The hot-air balloon

D．The mobile crane小题2:In the second paragraph, the author tells_________________.

A．who suits bungee jumping

B．the principle of bungee jumping

C．the material used for bungee jumping

D．the danger of bungee jumping小题3:According to the last paragraph, the safety of the jumpers depends mainly on________.

A．the weight of the jumper

B．the height of the jumping place

C．the length of the cord

D．the speed of the falling小题4:The purpose of writing this passage is to__________.

A．teach people how to carry out a bungee jumping

B．remind people of the danger of bungee jumping

C．advise people not to take the risk of bungee jumping

D．introduce some knowledge about bungee jumping

[背景材料]

某工程，建设单位和施工单位按《建设工程施工合同(示范文本)》签订了施工合同，在施工合同履行过程中发生如下事件。

事件1：工程开工前，总监理工程师主持召开了第一次工地会议。会上，总监理工程师宣布了建设单位对其的授权，并对召开工地例会提出了要求。会后，项目监理机构起草了会议纪要，由总监理工程师签字后分发给有关单位；总监理工程师主持编制了监理规划，报送建设单位。

事件2：施工过程中，由于施工单位遗失工程某部位设计图纸，施工人员凭经验施工，现场监理员发现时，该部位的施工已经完毕。监理员报告了总监理工程师，总监理工程师到现场后，指令施工单位暂停施工，并报告建设单位。建设单位要求设计单位对该部位结构进行核算。经设计单位核算，该部位结构能够满足安全和使用功能的要求，设计单位电话告知建设单位，可以不作处理。

事件3：由于事件2的发生，项目监理机构认为施工单位未按图施工，该部位工程不予计量；施工单位认为停工造成了工期拖延，向项目监理机构提出了工程延期申请。

事件4：主体结构施工时，由于发生不可抗力事件，造成施工现场用于工程的材料损坏，导致经济损失和工期拖延，施工单位按程序提出了工期和费用索赔。

[问题]

指出事件1中的不妥之处，写出正确做法。