Answer :
In engineering, particularly in the field of civil engineering, asphalt is graded according to its performance in various temperature conditions. This grading system is known as PG, or Performance Grade. The two numbers in a PG grade represent the average 7-day maximum pavement design temperature and the minimum pavement design temperature, both measured in degrees Celsius. These numbers help in selecting the appropriate asphalt binder for specific climatic conditions.
Let's review each option to determine which is unlikely to represent a realistic asphalt performance grade on Earth:
PG 52-22: This grade indicates a maximum temperature of 52°C and a minimum temperature of -22°C. This range is plausible on Earth in regions with moderate climates.
PG 60-28: This grade means a maximum temperature of 60°C and a minimum of -28°C. Such a range could be used in areas with hotter climates.
PG 82-34: This grade refers to a maximum temperature of 82°C and a minimum temperature of -34°C. This range could be suitable for extremely hot and cold regions.
PG 142-10: A maximum temperature of 142°C is extraordinarily high for Earth's conditions. Such a temperature is far above what would be expected even in the hottest climates on Earth, making it highly unlikely.
PG 46-112: The minimum temperature of -112°C is far below any natural temperature found on Earth. This grade is also unlikely due to its extreme range.
PG 46-28: This grade is reasonable, with a maximum temperature of 46°C and a minimum temperature of -28°C, making it possible for certain regions on Earth.
Looking at the options provided, PG 142-10 (D) and PG 46-112 (E) are the asphalt grades that are unlikely to occur because they specify extreme temperatures that are not typical in Earth's natural environments.
