Which landform would be hardest to hike through ? why?

The density of a substance is 4.0 g/cm3. if a sample of the substance has a volume of 25 cm3 then what is the mass

What properties of a moving object are used in determining the object's energy of motion

Atelevision set that has been running for a while heats up even the air around it. which two laws of thermodynamics could be used to analyze this scenario