Answer: The first one is A and C
Explanation:
Answer:
(a)The work done by the man is -15.03J.
(b)The force exerted on the object is 127.4N.
Explanation:
Mass of the object pulled by the man is -13kg
Object is lifted 11.8 cm vertical with his teeth it means (displacement = +11.8cm = +0.118m)
Acceleration due to gravity is 
(a) <u>Calculating the work done</u>:
Work done = mgh
Where "m" is mass of an object, "g" is acceleration due to gravity and "h" is the displacement.
The work done by the man is -15.03J.
(b) <u>Calculating the force</u>:
Probably the man and the object are close to the exterior of the earth. If the rigidity required to maintained the object of consistent velocity interior the gravitational field of the earth is 
Thus the weight of the object is balanced by the force of the man's teeth on the object. That is
F = mg
F = 127.4N
The force exerted on the object is 127.4N.
Hertzsprung-Russell <span>Diagram</span>
The correct answer is - C. Crustal plates, crustal plates.
The movement of the crustal plates of the Earth is the reason why the geologic processes are occurring on our planet. With their movement, the crustal plates manage to create lot of pressure, open up gaps for the magma from the mantle, as well as make adjustments deeper into the ground.
Because of the adjustments deep into the ground, or rather the crust, lot of force is released, manifested as strong and very quick vibrations, better known as earthquakes.
The gaps that are opening between the plates let the magma reach the surface, thus enabling the volcanic activities on the planet.
The pressure from the plates' collision makes the land lift up slowly, and over time a mountain range starts to form because of the continuous lifting up of the area.
Thermal energy always flows spontaneously from the body that is at a higher temperature to the body that has a lower temperature.
In this case, the thermal energy flows from the hot beverage that is at the temperature t1 to the ice cube at the temperature t2 until the two reach the same temperature t3.
Where:
t1> t2 <t3.
The ice cube would emit heat if the temperature of the liquid with which it comes in contact with the smaller than that of the ice.
