Research topic: Day-to-day operations at the Spindletop oil field during its 1901 boom in Texas. Source 1: A 2018 peer-reviewed history article that reconstructs drilling workflows at Spindletop using corporate archives and newspapers; includes synthesized charts and interpretations. Source 2: A 1937 Works Progress Administration oral-history transcript in which a former roustabout recalls rig practices from 1901; retrospective testimony. Source 3: A 1921 political cartoon lampooning the social impact of the oil boom; an artifact reflecting attitudes after the initial strike. Source 4: The drilling foreman's daily logbook from January–March 1901 for the Lucas well at Spindletop, with handwritten entries on mud weight, bit changes, crew rosters, and timing of strikes.

Which source is a primary source that directly documents day-to-day operations at Spindletop in 1901?

Research topic: Measuring ecological responses of coastal marshes to recent hurricanes along the Gulf Coast. Source 1: A 2019 peer-reviewed meta-analysis synthesizing 48 studies on post-hurricane marsh resilience; includes statistical models and summary tables. Source 2: A research team's 2022 raw sensor dataset of hourly salinity and water-level readings from three Gulf Coast marsh sites, with scanned field notebooks and calibration records. Source 3: A 2020 U.S. geological agency field survey packet containing original transect notes, GPS-tagged photographs, and quadrat measurements collected one month after a hurricane. Source 4: A 2021 coastal ecology textbook chapter overviewing storm impacts on wetlands, with diagrams and citations.

Which pair lists only primary sources for measuring marsh conditions after hurricanes in this study?

Research topic: Policing practices in a large U.S. city during the 1990s. Source 1: A 2005 peer-reviewed sociology article that analyzes 1990s policing in the city using internal memos, arrest ledgers, and interviews; includes theory and data visualizations. Source 2: A 1994 internal memo from the police chief to patrol supervisors detailing checkpoint procedures. Source 3: A 1992 city-council hearing transcript with resident testimony about traffic stops, recorded by the clerk. Source 4: A 2019 op-ed by a retired officer reflecting on practices in the 1990s, offering personal opinions and interpretations.

Which source should be classified as a secondary source for a study of 1990s policing practices, even though it relies on primary documents?

Research topic: The evolution of Tejano music production practices from 1970 to 1995 in Texas. Source 1: 1982 studio session track sheets and an engineer's annotated mix notes from a San Antonio label's archive. Source 2: A 1994 live performance video captured by a local television crew, preserving the original audio-visual recording. Source 3: A 2010 museum exhibit catalog on Tejano music featuring curator essays alongside high-resolution photographs of instruments, lyric sheets, and studio contracts from the period. Source 4: A 2016 musicology monograph that conducts harmonic and production analysis across albums from 1970–1995 and situates them in cultural context.

Which source contains both primary and secondary elements, making its classification depend on how it is used?

Research Topic: The 1900 Galveston Hurricane's immediate impact on residents.

Sources:

1. Excerpted pages from the handwritten diary of a Galveston resident dated Sept. 7–12, 1900, describing conditions during and after landfall.
2. A 2021 peer-reviewed historical analysis comparing municipal mortality ledgers from Galveston and Houston to reassess the death toll.
3. U.S. Weather Bureau telegram logs sent between island observers and the central office on Sept. 8–9, 1900.
4. A 1935 Works Progress Administration oral history transcript of a survivor recalling the storm.
5. A 2015 museum exhibition catalog that curates photographs and artifacts from the storm with interpretive essays.

Which TWO sources are primary sources that provide contemporaneous firsthand evidence of the 1900 storm as it unfolded?

Research Topic: Off-target effects in CRISPR-Cas9 gene editing.

Sources:

1. A 2015 laboratory study reporting whole-genome sequencing of edited human cell lines, including methods, results, and links to raw data.
2. A 2023 systematic review and meta-analysis synthesizing published off-target rates across 120 studies.
3. A public data repository entry containing raw sequencing files and sample metadata from a specific CRISPR experiment.
4. A journal editorial exploring ethical implications of off-target edits while summarizing recent findings.
5. A university news release announcing a new CRISPR protocol and quoting a lead researcher.

Which TWO sources are primary sources providing original empirical evidence suitable for inclusion as direct evidence in a methods-focused research paper?

Research Topic: Migrant experiences along the Texas–Mexico border in the 1990s.

Sources:

1. 1996 field notes and audio interview recordings collected by a sociologist in Brownsville shelters.
2. A 2022 theoretical monograph interpreting border narratives using critical theory, quoting published memoirs and interviews.
3. 1995 U.S. Border Patrol monthly apprehension logs for the Rio Grande Valley sector, released via FOIA.
4. A 2008 documentary film built from original on-camera interviews with migrants recorded in 2007.
5. A 2019 policy brief from a nonpartisan institute summarizing trends in crossings since 1990.

Which source is best classified as a secondary source even though it contains direct quotations from migrants?

Research Topic: Performance practices in late-1940s Texas conjunto music.

Sources:

1. A 2018 peer-reviewed article by a musicologist synthesizing archival recordings and prior scholarship to argue about accordion technique.
2. A 1952 letterpress concert poster advertising a San Antonio dance hall performance featuring a well-known conjunto duo.
3. Two 1948 acetate discs capturing a live conjunto performance recorded in a local studio, digitized without modern overdubs.
4. A 2020 annotated edition of a 1949 accordionist's diary, reproducing original entries alongside scholarly notes.
5. A 2021 museum-curated streaming compilation assembling tracks from various 1940s ensembles.

For a study focused on original performance practices of late-1940s Texas conjunto, which source is the strongest primary source?