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: If it has ions, it is an electrolyte
Explanation:
Let's start by explaining that electrolytes are compounds that contain charged particles or<u> ions</u>, which can be cations (positive ions) or anions (negative ions).
So, it is this composition that makes an electrolytic material conduct electricity.
In this sense, the way to identify if a material is an electrolyte or not, is knowing whether it is composed of ions or not.
Answer:
Distance= 2.3864m
Explanation:
So that the balance is in equilibrium parallel to the floor, we must match the moment each man makes with respect to the pivot point.
In many cases the point of application of force does not coincide with the point of application in the body. In this case the force acts on the object and its structure at a certain distance, by means of an element that transfers that action of this force to the object.
This combination of force applied by the distance to the point of the structure where it is applied is called the moment of force F with respect to the point. The moment will attempt a rotation shift or rotation of the object. The distance from the force to the point of application is called the arm.
Mathematically it is calculated by expression:
M= F×d
The moment caused by the first man is:
M1= 75kg × (9.81m/s²) × 1.75m= 1287.5625 N×m
The moment caused by the second man must be equal to that caused by the first by which:
M2= 1287.5625 N×m= 55kg × (9.81m/s²) × distance ⇒
⇒distance= (1287.5625 N×m)/( (55kg × (9.81m/s²) )= 2.3864m
At this distance from the pivot point, the second should sit down so that the balance is balanced parallel to the ground.
Answer:

Explanation:
Momentum is the product of mass and velocity.

The mass of the truck is 2,000 kilograms and the velocity is 35 meters per second.

Substitute the values into the formula and multiply.

The truck's momentum is <u>70,000 kilograms meters per second.</u>
Choice-C is a correct statement.