Lava flows are the least hazardous of all processes in volcanic eruptions. How far a lava flow travels depends on the flows temperature, silica content, extrusion rate, and slope of the land. A cold lava flow will not travel far and neither will one that has a high silica content. Such a flow would have a high viscosity<span> (a high resistance to flow). A basalt flow like those in Hawai'i have low silica contents and low viscosities so they can flow long distances. Such a flow can move as far away as 4 km from its source and have a thickness of 10 m (Bryant, 1991). These flows can move at rates of several kilometers per hour (Scott, 1989). </span><span>More silica-rich flows can move as far away as 1.3 km from their sources and have thicknesses of 100 m (Bryant, 1991). These flows can move at rates of a few to hundreds of meters per hour (Scott, 1989). If a lava flow is channelized or travels underground in a lava tube then the distance it travels is greatly extended.</span>
<h2>Answer: D. Rayleigh wave
</h2>
Rayleigh waves are a type of surface acoustic wave that causes particles on the surface of solids to travel along an elliptical path in the vertical plane that contains the direction of wave propagation.
These waves include longitudinal (P wave) and transverse (S wave) movements whose amplitude decreases exponentially as the distance from the surface increases.
This means Rayleigh waves are generated by the interference between the P and S waves on the surface of the Earth.
The answer is seafloor spreading
Answer:
C. supply and demand
Explanation:
<u>In the system of the market economy, the decisions about economic processes are based on the of the people (how much they need and buy something) and the needs of the supply (needs for natural resources, goods, and things which can be bought). </u>
A market economy also means the pricing of the goods is based on the demand for them. If products are not in demand and bought by the customers, it’s the price and supply goes down. Once the demand for the product grows, the profit is made.
The final goal is the price which is <u>equilibrium</u>, meaning goods are supplied exactly by the demand and with the fixed price that makes the process possible. This equilibrium should also provide the profit for the supplier.
