what is amethyst? bc i have an amethyst crystal, my aunt says it helps with bad dreams and stress but how does it help, i also have green quartz, clear quartz and rose quartz

The blue segment below is a diameter of oo. what is the length of the radius of the circle?

Plz asap can someone find the answer or the mark scheme or anything plzzz you : ) ‘it's perfectly understandable that hundreds of millions of people around the world live close to volcanoes’ use evidence to support this statement. (6 marks)

In the von thunen model of agricultural land use, what is produced closest to the city epicenter? a. dairy, vegetables, and fruits b. field crops, such as corn and wheat c. beef and other animal products d. wood and lumber