Summary:
Explanation: We need to convert units of time, currency, and length based on standard conversion factors.
Conversions:
- 1) One quarter of an hour is 60 minutes / 4 = 15 minutes.
- 2) One sixth of a day is 24 hours / 6 = 4 hours.
- 3) One half of a year is 12 months / 2 = 6 months.
- 4) One half of a ruble is 100 kopecks / 2 = 50 kopecks.
- 5) One fifth of a meter is 100 cm / 5 = 20 cm.
Answer: 1) 15 min, 2) 4 hours, 3) 6 months, 4) 50 kopecks, 5) 20 cm