In legacy hard-copy output, typewriter-style computer terminals (teleprinters/TTYs) typically print at which characteristic rate under standard operating conditions?

Introduction:
Before graphical displays and high-speed printers were commonplace, many systems relied on electromechanical teleprinters (typewriter terminals) for human-readable output. Understanding their approximate throughput helps contextualize early data processing speeds and user experience.

Given Data / Assumptions:

• Device: typewriter-style terminals (e.g., Teletype models) used with computers and communications equipment.
• Metric of interest: steady-state character printing rate.
• Common historical speeds include around 10 characters per second (cps) for general-purpose units.

Concept / Approach:
Classic teleprinters often operated near 110 baud on asynchronous lines, effectively producing approximately 10 cps of readable output, which corresponds to roughly 600 characters per minute (cpm). Faster specialized printers existed, but the typical baseline for many educational and commercial setups hovered around 10 cps, balancing mechanical reliability and cost.

Step-by-Step Solution:
1) Associate teleprinter-era speeds with common baud rates (e.g., ~110 baud → ~10 cps for 10-bit frames).2) Recognize the mechanical limits of impact printing mechanisms of that period.3) Compare offered options: 10 cps aligns with common historical devices; 120 cps (7200 cpm) far exceeds typical typewriter mechanisms.4) Conclude that 10 characters per second is the characteristic rate.

Verification / Alternative check:
Documentation for popular teleprinters (e.g., Teletype Model 33) cites rates around 10 cps, corroborating the standard classroom/exam value.

Why Other Options Are Wrong:

• 120 cps: beyond typical typewriter terminal capability; more akin to later line printers.
• 120 cpm: equals 2 cps, unusually slow for common teleprinters.
• 1200 cpm: equals 20 cps; while some faster terminals existed, 10 cps is the widely referenced standard rate.
• None of the above: invalid because 10 cps is correct.

Common Pitfalls:
Mixing cps and cpm or assuming modern printer speeds apply to electromechanical teleprinters.

Final Answer:
10 characters per second