7 While the potential for spontaneous communication between a human and a machine may seem exciting, this possibility concerns some people. Some experts worry about people’s attachment to these machines and fear that the art of successful human-to-human conversation will be undeveloped in younger generations. They worry that people won’t be able to display the right emotion or tone in conversations because they haven’t been practicing those skills. Others fear that machines will take over functions that were traditionally performed by humans, such as customer service.

8 Another concern often associated with the development of new technology is the invasion of privacy. When people use certain speech-recognition applications, they leave behind an audio track of their speech. When you ask a VPA for directions, your speech is often sent and saved to a remote server for processing. This digital trail may lead to data mining, or the collection of large quantities of personal data.

What is the main idea of paragraphs 7 and 8?

2 The Nile is the longest river in the world. When including the headwaters of both the Blue Nile and the White Nile, the Nile measures more than 4,100 miles. The White Nile begins in Rwanda, and the Blue Nile begins in Ethiopia; they meet in Sudan to form the Nile River, which flows through Egypt to the Mediterranean Sea. The river covers terrain that includes mountains, deserts, gorges, lakes, valleys, dams, waterfalls, and large cities. It flows through the largest lake in Africa; it winds through capital cities; it grazes ancient cities as well as world-renowned antiquities such as the pyramids.

Which detail from paragraph 2 supports the idea that the Nile River spans diverse areas?

3 Until Scaturro and Brown’s expedition in 2004, no one had successfully traveled the length of the river beginning from the Blue Nile, which is often considered the source of the Nile because it provides more than 85 percent of the water in the Nile River. Scaturro and Brown launched their watercraft from the Springs of Sakala, the origins of the Blue Nile in the Ethiopian highlands, in late December 2003. Their watercraft included two 16-foot inflatable rafts and a two-person kayak. A small support crew, which at times included a journalist, an archaeologist, a photographer, and a hydrologist, joined the men and aided with some of the planning. But the bulk of the navigating, paddling, and filming—Brown was shooting their adventure with a 70-pound IMAX camera—fell to Scaturro and Brown.

4 The pair traveled 3,250 miles in four months. During their journey they encountered disease-carrying mosquitoes, sand storms, extreme heat, and armed bandits. Several stretches of the river pass through areas of unrest or civil war. Many sections of the Nile have life-threatening rapids, leading some to liken the river to Mount Everest in terms of adventure and danger. Scaturro and Brown’s boats flipped in the white water more than once. A crocodile attacked Brown’s kayak and took a bite out of his oar. In several areas the river proved impassible, and the team was forced to briefly portage their boats or send the boats down dangerous waterfalls or rapids unmanned while they bypassed the area on foot.

5 But for all the dangers they encountered, they also met with awe-inspiring sights and experiences. Scaturro noted in his journal that for much of their time on the Nile in Sudan, they saw “absolutely not a single other tourist, adventurer, traveler, or any other westerner.... Basically, we have had the entire Nile River to ourselves. What an adventure.”

Based on paragraph 5, the reader can infer that for Scaturro and Brown —

6 From the white-water gorges of Ethiopia to the desert plains of Sudan to the urban pollution near heavily populated Egyptian cities, Scaturro and Brown experienced the best and the worst of the Nile. Their journey revealed to them that the Nile is a unifying thread of civilization in northeastern Africa. All told, the Nile and its main tributaries flow through 11 African countries: Burundi, the Democratic Republic of Congo, Egypt, Eritrea, Ethiopia, Kenya, Rwanda, South Sudan, Sudan, Tanzania, and Uganda—countries with diverse cultures, beliefs, and environments that are all connected by the mighty river. “One theme we hope this expedition highlights is that the Nile brings people of different faiths and cultures . . . together,” Brown says.

The details in paragraph 6 support the idea that —

8 A celebrity is all about fame—temporary, superficial fame, usually for qualities that are easy to see: a pretty face, a good hook shot, a great dance move. A hero, by contrast, is about character—qualities beneath the surface that aren’t visible until they prompt action. Qualities like courage, hope, compassion, and perseverance.

The author organizes paragraph 8 by —

Read this sentence about heroes.

They truly hold our world together, through their unselfish devotion to helping others, supporting families, teaching children, protecting the environment.

The author includes this sentence most likely to emphasize that —

5 The billboard produces 96 liters (about 25 gallons) of water a day. This can supply hundreds of families with water each month. The partnership of UTEC and Mayo DraftFCB has not yet decided whether to build more billboards, and if so, where to locate them. But the citizens of Lima and other cities in arid regions around the world are hopeful.

What is the main idea of paragraph 5?

Which sentence supports the idea that creating structures from shipping containers is cost-efficient?

Read this sentence from the selection.

Or perhaps she saw, in a way that we could not, that the photograph misrepresented her in some crucial respect, that in its dim, mechanical eye it had failed to see into her real being.

Which of these is the author suggesting in this sentence?

4 This is where the “pain” comes in. You see, to reach Antarctica, ships must pass through a notoriously violent area of ocean called the Drake Passage, considered to be the roughest stretch of sea on the planet.

In paragraph 4, what does the word notoriously mean?

1 Yellowstone National Park extends across a unique area of land in Wyoming, Montana, and Idaho. Thousands of geothermal vents that lie just below the earth’s surface cover this vast region. Geothermal vents are deep holes in the ground that release built-up pressure in the form of steam and scalding-hot water. The temperature of the ground near these hot spots can rise to more than 150 degrees Fahrenheit. During a trip to Yellowstone, microbiologist Rusty Rodriguez noticed something peculiar. He observed many plants thriving in the searing soil despite these intense conditions. Rodriguez wondered how these plants were able to flourish in such extreme temperatures while other plants in similar or milder environments perish.

What is paragraph 1 mostly about?

3 Concrete is one of the most important building materials. It was even used by the ancient Romans to build massive structures such as the Colosseum. Today it is used to construct highways, bridges, and high-rise buildings. In fact, concrete demand has doubled in the last decade. Concrete production now accounts for 5% of the world’s carbon emissions, which is harmful to the environment.

Which statement best expresses the main idea of paragraph 3?

6 In 2011 self-healing concrete was used to construct a lifeguard station near a lake in the Netherlands. Lifeguard stations are susceptible to damage by water and weather. With the help of Jonkers’ bioconcrete, the lifeguard station has remained intact. Bioconcrete has been used on the floors and roofs of parking garages. It has even been used to reconstruct a canal and irrigation system in Ecuador.