While researching a topic, a student has taken the following notes:

• In 2018 researchers Adwait Deshpande, Shreejata Gupta, and Anindya Sinha were observing wild macaques in India’s Bandipur National Park.
• They saw macaques calling out to and gesturing at humans who were eating or carrying food.
• They designed a study to find out if the macaques were intentionally communicating to try to persuade the humans to share their food.
• In the study trials, macaques frequently called out to and gestured at humans holding food.
• In the study trials, macaques called out to and gestured at empty-handed humans less frequently.

It has long been thought that humans first crossed a land bridge into the Americas approximately 13,000 years ago. ______blank based on radiocarbon dating of samples uncovered in Mexico, a research team recently suggested that humans may have arrived more than 30,000 years ago—much earlier than previously thought.

While researching a topic, a student has taken the following notes:

• John Carver was one of the 41 signatories of the Mayflower Compact.
• The Mayflower Compact was a legal agreement among the pilgrims that immigrated to Plymouth Colony.
• It was created in 1620 to establish a common government.
• It states that the pilgrims who signed it wanted to “plant the first colony in the northern parts of Virginia” under King James.
• Carver became the first governor of Plymouth Colony.

For years, biologists have experimented with using grime-eating bacteria rather than harsh chemicals to clean artworks, and results have been impressive overall. ______blank these bacterial strains—which can metabolize centuries’ worth of oil, glue, dirt, and other surface impurities without creating harmful byproducts—have proven more effective than traditional chemical cleaning methods.

While researching a topic, a student has taken the following notes:

• In 1971, experimental musician Pauline Oliveros created Sonic Meditations.
• Sonic Meditations is not music but rather a series of sound-based exercises called meditations.
• Each meditation consists of instructions for participants to make, imagine, listen to, or remember sounds.
• The instructions for Meditation V state, “walk so silently that the bottoms of your feet become ears.”
• Those for Meditation XVIII state, “listen to a sound until you no longer recognize it.”

While researching a topic, a student has taken the following notes: 

• In 2013, paleontology professor Hesham Sallam and his students from Mansoura University in Egypt made a discovery.
• The team found a partial dinosaur skeleton at a site in Egypt’s Dakhla Oasis.
• The skeleton belonged to a dinosaur species that lived approximately 80 million years ago.
• The new species was named Mansourasaurus to recognize the team that discovered it.

Some members of the US Supreme Court have resisted calls to televise the court’s oral arguments, concerned that the participants would be tempted to perform for the cameras (and thus lower the quality of the discourse). ______blank the justices worry that most viewers would not even watch the full deliberations, only short clips that could be misinterpreted and mischaracterized.

While researching a topic, a student has taken the following notes:

• In 2013, archaeologists studied cat bone fragments they had found in the ruins of Quanhucun, a Chinese farming village.
• The fragments were estimated to be 5,300 years old.
• A chemical analysis of the fragments revealed that the cats had consumed large amounts of grain.
• The grain consumption is evidence that the Quanhucun cats may have been domesticated.

While researching a topic, a student has taken the following notes:

• Some powerful works of literature have so influenced readers that new legislation has been passed as a result.
• The Interesting Narrative of the Life of Olaudah Equiano (1789) is the autobiography of a man who endured slavery on both sides of the Atlantic.
• Equiano’s book contributed to the passage of the Slave Trade Act of 1807.
• The Jungle (1906) is a fictional work by Upton Sinclair that describes unsanitary conditions in US meatpacking plants.
• Sinclair’s book contributed to the passage of the Pure Food and Drug Act in 1906.

Researchers believe that pieces of hull found off Oregon’s coast are from a Spanish cargo ship that was lost in 1697. Stories passed down among the area’s Confederated Tribes of Siletz Indians support this belief. ______blank Siletz stories describe how blocks of beeswax, an item the ship had been carrying, began washing ashore after the ship was lost. 

Jhumpa Lahiri’s story collection Interpreter of Maladies features multiple stories about romantic relationships. In “This Blessed House,” newlyweds argue over whether to replace items left by the previous owners of their new home. ______blank in “A Temporary Matter,” a husband and wife attempt to rekindle their relationship during a four-night blackout.

Before the 1847 introduction of the US postage stamp, the cost of postage was usually paid by the recipient of a letter rather than the sender, and recipients were not always able or willing to pay promptly. ______blank collecting this fee could be slow and arduous, and heaps of unpaid-for, undeliverable mail piled up in post offices.

In Gothic architecture, flying buttresses are large arches that help support a building’s exterior walls. Before the Gothic era, cathedrals’ heavy ceilings had to be supported by thick, short walls, but the invention of flying buttresses eliminated this need. ______blank Gothic cathedrals could be built with thinner, higher walls.

Small, flat structures called spatulae are found at the tips of the hairs on a spider’s leg. These spatulae temporarily bond with the atoms of whatever they touch. ______blank spiders are able to cling to and climb almost any surface.

While researching a topic, a student has taken the following notes:

• Platinum is a rare and expensive metal.
• It is used as a catalyst for chemical reactions.
• Platinum catalysts typically require a large amount of platinum to be effective.
• Researcher Jianbo Tang and his colleagues created a platinum catalyst that combines platinum with liquid gallium.
• Their catalyst was highly effective and required only trace amounts of platinum (0.0001% of the atoms in the mixture).