1. Which of the following questions is NOT appropriate for scientific investigation?

A. How can we reduce greenhouse gas emissions?
B. Is there intelligent life beyond Earth?
C. What is the meaning of life?
D. Does free will exist?

Correct answer: C

Rationale: Science deals with observable, measurable phenomena using evidence-based methods. Questions about subjective experiences and abstract concepts like meaning fall outside the realm of scientific inquiry.

2. How does the potential energy of an object change when it is compressed?

A. Potential energy decreases
B. Potential energy increases
C. Potential energy remains constant
D. Potential energy becomes zero

Correct answer: b

Rationale: When an object is compressed, it stores potential energy due to its altered position or configuration.

3. In the process of cellular respiration, glucose is broken down to produce energy. What is the main waste product released?

A. Water
B. Carbon dioxide
C. Oxygen
D. Protein

Correct answer: B

Rationale: The correct answer is B: Carbon dioxide. During cellular respiration, glucose is broken down in the presence of oxygen to produce energy in the form of ATP. One of the main waste products released in this process is carbon dioxide. Carbon dioxide is a byproduct of the metabolic reactions occurring in cells and is expelled from the body through exhalation. Water is also produced during cellular respiration, but it is not the main waste product released. Oxygen is required for cellular respiration to occur, and protein is a macromolecule and not a waste product of cellular respiration.

4. Which sentence uses parallel structure correctly?

A. I enjoy reading, watching movies, and to spend time with friends.
B. Reading, watching movies, and spending time with friends are all activities I enjoy.
C. like to read, watch movies, and spend time with friends.
D. Reading, movies, and friends are all things I enjoy.

Correct answer: B

Rationale: Parallel structure means using the same grammatical form for elements in a list. Option (b) uses parallel gerunds ("reading," "watching," "spending"), making it the correct choice.

5. The primary function of the placenta during pregnancy is to:

A. Produce insulin
B. Facilitate gas exchange between mother and fetus
C. Excrete waste products from the fetus
D. All of the above

Correct answer: D

Rationale: The correct answer is D, 'All of the above.' The placenta serves multiple crucial functions during pregnancy. It facilitates gas exchange between the mother and fetus, ensuring the transfer of oxygen and nutrients while removing carbon dioxide and waste products. Additionally, the placenta produces hormones like insulin that help regulate the mother's metabolism and support the development of the fetus. Therefore, the placenta plays a vital role in maintaining a healthy environment for the growing fetus by providing essential nutrients, removing waste, and regulating hormonal balance.