1. What is a contraceptive method that uses hormones to prevent ovulation?

A. Spermicide
B. Barrier method (condom, diaphragm)
C. Combined oral contraceptive pill
D. Intrauterine device (IUD)

Correct answer: C

Rationale: The correct answer is C: Combined oral contraceptive pill. This method uses hormones, such as estrogen and progestin, to prevent ovulation, thicken cervical mucus to block sperm, and thin the uterine lining to prevent implantation of a fertilized egg. Spermicide (A) is a chemical that kills sperm but does not prevent ovulation. Barrier methods (B) like condoms and diaphragms physically block sperm from reaching the egg. Intrauterine devices (IUDs) (D) are inserted into the uterus and work by either releasing hormones or creating a barrier to prevent fertilization, but they do not specifically target ovulation.

2. Which of the following is the main function of the heart?

A. To filter blood
B. To exchange gases
C. To pump blood throughout the body
D. To produce hormones

Correct answer: C

Rationale: Rationale: The main function of the heart is to pump blood throughout the body. The heart is a muscular organ that works as a pump to circulate blood, which carries oxygen and nutrients to the body's tissues and removes waste products. Option A is incorrect because the kidneys are responsible for filtering blood. Option B is incorrect because the exchange of gases, such as oxygen and carbon dioxide, occurs in the lungs. Option D is incorrect because hormone production is primarily carried out by endocrine glands such as the pituitary gland and the thyroid gland.

3. What is the half-life of a radioactive isotope, and how does it relate to its decay rate?

A. The time it takes for half of the initial sample to decay.
B. The time it takes for all the sample to decay.
C. The rate at which new isotopes are created.
D. The energy released during decay.

Correct answer: A

Rationale: Half-life tells the time it takes for half of the original radioactive nuclei to decay, offering an indication of the decay rate.

4. When writing a blog post, consider including:

A. Long, detailed paragraphs for comprehensive coverage.
B. Frequent use of emojis and informal slang for a casual tone.
C. Engaging headlines, subheadings, and bullet points for scannability.
D. ense academic vocabulary to sound intellectual.

Correct answer: C

Rationale: Blog posts require engaging formatting and concise writing for readers who scan and skim. Headlines, subheadings, and bullet points improve readability.

5. What effect does doubling the net force applied to an object have on its acceleration, assuming mass remains constant?

A. Acceleration doubles
B. Acceleration is halved
C. Acceleration remains the same
D. Acceleration quadruples

Correct answer: a

Rationale: According to Newton's second law (F = ma), if mass remains constant and force doubles, acceleration also doubles.

6. Which state of matter has particles that are highly organized in a fixed pattern and vibrate in place?

A. Solid
B. Liquid
C. Gas
D. Plasma

Correct answer: a

Rationale: In solids, particles are tightly packed in an ordered arrangement and vibrate around fixed positions, giving solids a definite shape and volume.