This molten rock is called magma when it is beneath the surface and lava when it erupts or flows from a volcano. Along with lava, volcanoes also release gases, ash, and rock. ... Volcanoes form at the edges of Earth's tectonic plates
Answer:
The magnetic field is
Explanation:
From the question we are told that
The mass of the metal rod is 
The current on the rod is 
The distance of separation(equivalent to length of the rod ) is 
The coefficient of kinetic friction is 
The kinetic frictional force is 
The constant speed is 
Generally the magnetic force on the rod is mathematically represented as

For the rod to move with a constant velocity the magnetic force must be equal to the kinetic frictional force so

=> 
=> 
=> 
Answer:
C should be the correct answer,
Explanation:
The gas which produce heat in the atmosphere as it is increased is called a greenhouse gas. Gases like argon , nitrogen, and Oxygen etc. is not a greenhouse gas. Since O3 is not a greenhouse gas it cannot produce heat in the atmosphere .
Hope you understand,
Answer: $4,500
Explanation: 1% of $30,000 would be $300. If you multiply that by 15, you get $4,500, so 15% of 30,000 is 4,500.
This would be the definition of gravitational force, I believe. The force of attraction between 2 objects based on the mass of the objects.