Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 30 to 34 

     As computer use becomes more common, the need for security is more common than ever. One of the greatest security threats in the online world is computer hacking.  

     Computer hacking is the unauthorized access to a computer or network of computers. Hackers are people who illegally enter systems. They may alter or delete information, steal private information, or spread viruses that can damage or destroy files. But how exactly can a hacker get into a system to do these things?  

     Most hackers use information called protocols that are built into computer software. These protocols allow computer to interact with one another. Protocols are sort of like computer police officers. When a computer connects to another system, the protocols check to see if the access is valid. The protocols can also determine how much information can be shared between the two systems. Hackers can manipulate the protocols to get unlimited access to a computer system. 

     In fact, just the act of entering a computer network is considered hacking. This is commonly called passive hacking. Passive hackers get a rush from just being able to access a challenging system like a bank or military network. Another kind of hacker tries to do damage to a system. After hacking into systems, these hackers release viruses or alter, delete, or take information. Known as active hackers, they are, by far, the more dangerous of the two.  

     The easiest way to protect a system is with a good password. Long and unusual passwords are harder for hackers to guess. For even greater security, some online services now use “password-plus” systems. In this case, users first put in a password and then put in a second code that changes after the user accesses the site. Users either have special cards or devices that show them the new code to use the next time. Even if a hacker steals the password, they won’t have the code. Or if the hacker somehow gets the code, they still don’t know the password. 

What is the main idea of this reading?

On Sundays, many people take their cars to service stations _______

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 35 to 42 

      Scientists have discovered that for the last 160,000 years, at least, there has been a consistent relationship between the amount of carbon dioxide in the air and the average temperature of the planet. The importance of carbon dioxide in regulating the Earth's temperature was confirmed by scientists working in eastern Antarctica. Drilling down into a glacier, they extracted a mile-long cylinder of ice from the hole. The glacier had formed as layer upon layer of snow accumulated year after year. Thus, drilling into the ice was tantamount to drilling back through time.  

     The deepest sections of the core are composed of water that fell as snow 160,000 years ago. Scientists in Grenoble, France, fractured portions of the core and measured the composition of ancient air released from bubbles in the ice. Instruments were used to measure the ratio of certain isotopes in the frozen water to get an idea of the prevailing atmospheric temperature at the time when that particular bit of water became locked in the glacier.  

     The result is a remarkable unbroken record of temperature and of atmospheric levels of carbon dioxide. Almost every time the chill of an ice age descended on the planet, carbon dioxide levels dropped. When the global temperature dropped 9°F (5°C), carbon dioxide levels dropped to 190 parts per million or so. Generally, as each ice age ended and the Earth basked in a warm interglacial period, carbon dioxide levels were around 280 parts per million. Through the 160,000 years of that ice record, the level of carbon dioxide in the atmosphere fluctuated between 190 and 280 parts per million, but never rose much higher until the Industrial Revolution beginning in the eighteenth century and continuing today.  

     There is indirect evidence that the link between carbon dioxide levels and global temperature change goes back much further than the glacial record. Carbon dioxide levels may have been much greater than the current concentration during the Carboniferous period, 360 to 285 million years ago. The period was named for a profusion of plant life whose buried remains produced a large fraction of the coal deposits that are being brought to the surface and burned today.  

Which of the following does the passage mainly discuss?

The passage implies that the warmest temperatures among the periods mentioned occurred _______.

What is not considered hacking?

There are no problems with Dave. He seems ____ after in a proper way.

At Lunar New Year (Tet) festival, each ethnic group in Vietnam has its own culinary specialties ______ reflect the culture of their people and are used as offerings to worship their ancestors.

According to the passage, the Carboniferous period was characterized by________

Mick: "What a nice watch you're wearing."  

                     Olio: " ____________"