All the statements can be used to explain about Earth's magnetic field.
Earth's magnetic field is almost same to that of the bar magnet. The magnetic field of the earth occurs from its core. It has an inner core which is solid in nature. in the outer core, there is a motion of the liquid due to heat flow from the inner core to the core mantle boundary which proves that the outer core is liquid and moving. The Earth's core consists of iron and nickel as the Eddy currents in the iron and nickel liquid helps generating the Earth's magnetic field.
Hence, all the three statements are true and can be used to explain the Earth's magnetic field.
Answer:
1.414
Explanation:
Snell's law states:
n₁ sin θ₁ = n₂ sin θ₂
where n is the index of refraction and θ is the angle of incidence (relative to the normal).
The index of refraction of air is approximately 1. So:
1 sin 45° = n sin 30°
n = sin 45° / sin 30°
n = 1.414
Round as needed.
Answer:

It will take 10 seconds to travel 200m at a speed of 10m/s
Explanation:
HOPE THAT THIS IS HELPFUL.
HAVE A GREAT DAY.
The river that flows through Rome is the Tiber.
wavelength = speed/frequency
==> freq. = speed/wavelength = 342.5/0.75 = 456.67 Hz.