Which techniques can scientists use to determine the characteristics of Earth's layers? Select the two correct answers. conduct experiments about how minerals change under high pressure

study how seismic waves travel through different layers

examine the behavior of minerals at extremely low temperatures

use X-rays to obtain a view of Earth's interior layers

drill deep mines to obtain samples from Earth's mantle and core

Iron reacts with sulfur to form iron sulfide. if 60 grams of iron reacts with sulfur to produce 90 grams of iron sulfide, how much sulfur has been used in the chemical reaction?

Aperson stands on a platform, initially at rest, that can rotate freely without friction. the moment of inertia of the person plus the platform is ip. the person holds a spinning bicycle wheel with its axis horizontal. the wheel has moment of inertia iw and angular velocity ωw. take the ωw direction counterclockwise when viewed from above. part a what will be the angular velocity ωp of the platform if the person moves the axis of the wheel so that it points vertically upward?

In an experiment, how can i change human errors? be specific.