GACE Computer Science - independent content foundations case studies
GACE Computer Science - independent content foundations · Put your knowledge to work in context.
This independent study page provides practice for GACE Computer Science - independent content foundations. Its editorial learning areas include Programming; Algorithms and computational thinking; Impacts, ethics and security; Data representation and information; Computing systems and networks. The questions develop subject knowledge and application through worked reasoning, distinctions between competing answers, and practical scenarios. Study the relevant guide before attempting a mixed set, then explain the evidence or calculation that supports each answer. Topics on this exam: Programming, Algorithms and computational thinking, Impacts, ethics and security, Data representation and information, and Computing systems and networks. The GACE Computer Science - independent content foundations case studies are 4 cases and about 2,594 words.
1The Attendance App Breach
A district's attendance web app has 12,000 student and staff accounts. Passwords are stored as unsalted SHA-256 hashes. An attacker exploits a SQL injection flaw in a report-export page and downloads the users table, including usernames, roles, and password hashes. The district's database volume is encrypted at rest, and the vendor argues that this protects the hashes.
569 words, about 3 min2Candidate Records at East Mercia Examinations Board
East Mercia Examinations Board stores records for 25,000 candidates. Each record contains an 8-digit candidate number, a 60-character name, and nine paper marks that are integers from 0 to 100. Records are currently kept in one unsorted binary file of fixed-length 150-byte records. On results day, 400 lookup requests per minute arrive by candidate number; the current system searches sequentially and misses the 2-second response target.
803 words, about 4 min3The Memory Hierarchy Upgrade Committee
A high school robotics team runs a simulation on 40 single-board computers. Each board has a 32 KB L1 cache with a 1-cycle hit time, a unified L2 cache with a 10-cycle hit time, and 100-cycle main memory. Profiling shows a 5% L1 miss rate; of those misses, 20% also miss in L2. A vendor offers two upgrades: (A) double L1 to 64 KB, which measurements suggest would halve the L1 miss rate but raise L1 hit time to 1.5 cycles; or (B) keep L1 unchanged and add a prefetcher that would cut the L2 miss rate from 20% to 10%.
609 words, about 3 min4The Slow Catalog Query
A public library's catalog database has 2.4 million rows in a table with columns id, title, author, year, subject, and checked out. The web catalog runs this query about 40 times per second: SELECT id, title FROM books WHERE author = ? ORDER BY title LIMIT 20. The only index is on author.
613 words, about 3 min