How long does it take to change a flat plain into mountains?

Which of these waves require a medium to travel through? Light wave Microwave Electromagnetic wave Sound wave

Push a notebook or some other object so that it slides across a table or desktop. What force causes the notebook to start moving? What force causes the notebook to stop moving? If you don't know the name of the forces, just describe them.

Waning gibbous meaning?

How long will it take to go 150 km [E] traveling at 50 km/hr?

Determine which heat transfers below are due to the process of conduction. A. you walk barefoot on a hot street and burn your toes B. when you get into a car with hot black leather in the middle of summer and your skin starts to get burned C.

What is the energy source that heats a contracting protostar?

What unit is kg divided by m/s^2

If the energy stored in the fully charged battery is used to lift the battery with 100-percent efficiency, what height is attained? Assume that the acceleration due to gravity is 9.8 m/s2m/s2 and is constant with height

How does the mass of an astronaut change when she travels from earth to the moon? how does her weight change?

If an object has a mass of 20 grams and a volume of 40 cm3, what is its density in g/cm3?