Explanation: In a freezing mixture, the common ratio of salt to ice is 1 part salt to 3 parts ice. This mixture lowers the freezing point of the ice, allowing it to absorb heat and freeze the substance effectively.

Explanation: When sugar dissolves in water, it forms a homogeneous solution without undergoing any major physical transformations like boiling or evaporation. The sugar molecules disperse throughout the water molecules, creating a uniform mixture. The process is physical, not chemical, and the water remains in its liquid state, although it may cool slightly depending on the conditions of the environment.

Explanation: Humidity refers to the amount of water vapor present in the air. It is typically measured in terms of absolute humidity, relative humidity, or specific humidity.

Explanation: A freezing mixture, typically made of ice and salt, can lower the temperature to about -23°C. This happens because the salt disrupts the ice's freezing point, causing the temperature to drop below the normal freezing point of water (0°C).

Explanation: Humidity refers to the amount of water vapor present in the air, and its unit is typically expressed as kilograms of water vapor per cubic meter of air (Kg/m³).

Explanation: This is the conversion factor between joules and calories, where 1 calorie is equivalent to 4.186 joules.