Answer: Sheila's top brick will be cooler than Ralph’s top brick, because Sheila’s started with more total energy, so less energy had to transfer for both her bricks to reach the same total energy.
Explanation:
Answer: The order from weakest to strongest is:

Explanation:
Dispersion force is the weakest intermolecular force. It is a temporary attractive force that come into action when the electrons in two neighboring atoms are at the positions which results in formation of temporary dipoles.
Dipole interaction is an attractive interaction between the positive end and negative end of the polar molecule.
Hydrogen bond is a weak bond between two adjacent molecules due to an electrostatic attraction between a hydrogen atom in a molecule with an electronegative atom of an adjacent molecule.
Single covalent bond is more stronger bond than the the interaction stated above because there is sharing of an electron between two atoms.
Ionic bond is the strongest bonds in which complete transfer of electrons is present. Due to high electronegativity difference between the bonded atoms there is a high electrostatic interaction between the oppositely charged ions which makes ionic bond strongest from all the other types of the bonds.
So, the order is:

Answer:
1.Electric generators (mechanical energy to electricity)
2.Windmills (mechanical energy to electricity)
Answer: The correct option is - The reaction container is cold.
Explanation: Endothermic reaction is a reaction in which the system absorbs energy from the surroundings, generally in the form of heat.
In this process, the surrounding becomes cold after loosing energy.
And here, the surrounding is reaction container and hence, will become cold by loosing its energy to the reaction mixture.