The answer to the first one is sublimation.
Answer: magnitude of the instantaneous angular velocity
Explanation:
Instantaneous angular speed is refered to as the magnitude of the instantaneous angular velocity. We should note that the instantaneous angular velocity is the rate that has to do with the rotation of an object in circular path.
Answer
• Improving the environmental performances
• Developing Green Mining technology
Explanation
The effect to the environment caused by opal mining are; impact on soils and geology, clearing of native vegetation disrupting flora and fauna, change in land use and effects of air quality.
Opal mining is currently examining environmental impacts and adopting measures that mitigate the impacts making the process less destructive to the environment.
With the current commitment to sustainability, opal companies are investing funds for Green Mining as a positive way to impact the environment before and after mining.
The movement of the tectonic plates is caused by convection currents in Earth´s mantle.
Answer: A) convection currents in Earth´s mantle.