Hey there!
Okay so, the Lithosphere is made out of Earth’s outermost layer, which is composed of rocks in the crust and the upper mantle that behave as brittle solids.
The Mantle is made up of rock containing silicon, iron, magnesium, aluminum, oxygen and other minerals.
The Core has two parts. The solid inner core made up of iron. The outer core is surrounded by a liquid composed of a nickel-iron alloy.
I hope this helps!
Answer:

Explanation:
The amplitude of he combined wave is:

A, is the amplitude from the identical harmonic waves
B, is the amplitude of the resultant wave
θ, is the phase, between the waves
The amplitude of the combined wave must be 0.6A:
