Correct Answer: D

Rationale: Acceleration is defined as the rate of change of velocity with respect to time. The correct formula to calculate acceleration is Acceleration = Time Change in Velocity. This formula specifically represents how much an object's velocity changes over a specified time period, providing a measure of the object's speed change rate. Choices A and B are incorrect as they do not represent the relationship between acceleration and time change in velocity. Choice C is incorrect as it involves time and distance, which are not directly related to acceleration.

Correct Answer: B

Rationale: The autonomic nervous system is correctly identified as the division responsible for the 'fight or flight' response, which readies the body to react to stressful situations. This system regulates involuntary bodily functions, such as heart rate, pupil dilation, and adrenaline release during stress. The somatic nervous system controls voluntary movements and skeletal muscle activity, not the automatic responses seen in the 'fight or flight' reaction. The peripheral nervous system connects the central nervous system to the body's organs and limbs, facilitating communication, while the central nervous system, comprising the brain and spinal cord, serves as the primary control center of the body, integrating and processing information.

Correct Answer: A

Rationale: The electron configuration of an atom refers to the arrangement of electrons in the atom's orbitals. This arrangement determines the atom's chemical properties and behavior. The number of protons in an atom's nucleus (option B) is known as the atomic number, which defines the element. The number of neutrons in an atom's nucleus (option C) contributes to the atom's mass number. The number of electrons in an atom's valence shell (option D) is important for understanding the atom's reactivity and bonding behavior, but the electron configuration specifically refers to how electrons are distributed among the different orbitals in an atom.

Correct Answer: A

Rationale: A mutation is defined as a change in the DNA sequence, which can occur due to various factors such as errors during DNA replication, exposure to mutagens (e.g., chemicals, radiation), or spontaneous changes. These alterations can lead to modifications in the genetic information carried by an organism, resulting in effects that can range from harmless variations to causing genetic disorders or diseases. Mutations play a crucial role in genetic diversity and evolution. Choices B, C, and D are incorrect as they do not accurately define what a mutation is. Option B is incorrect because mutations are not a type of protein but rather changes in DNA. Option C is incorrect because while mutations can occur during DNA replication, they are not considered a 'normal' part of the process as they can lead to genetic variations. Option D is incorrect because mutations can have a wide range of effects and are not always harmless variations.

Correct Answer: B

Rationale: The normal force from the floor is perpendicular to the direction of motion of the box, so it does not contribute to the work being done. Work is only done by forces acting in the direction of motion of an object. In this case, the normal force is acting at a right angle to the motion, hence it does not perform any work on the box. The person's pushing force, the gravitational force, and the frictional force are all acting in the direction of motion of the box, so they contribute to the work being done in moving the box across the floor.