Adding 15 and 27 gives 42. This basic arithmetic operation reinforces understanding of addition.

The sentence 'She walked to school.' uses the past tense verb 'walked' to indicate a completed action. This clearly differentiates it from the other options which use present or future tenses.

Under standard atmospheric conditions, water freezes at 0°C. This temperature is a fundamental scientific fact in the study of matter and its phases.

Multiplying 6 by 7 gives 42. This question tests basic multiplication skills in arithmetic.

The main idea represents the central message or primary point that an author wants to communicate. It is the foundation on which supporting details are built.

Dividing both the numerator and the denominator of 4/8 by 4 simplifies the fraction to 1/2. This demonstrates the concept of reducing fractions to their simplest form.

A simile directly compares two unlike things using connecting words such as 'like' or 'as'. This literary device is used to create vivid imagery and enhance descriptions.

Mars is commonly called the Red Planet because of its reddish appearance due to iron oxide on its surface. This is a well-known fact in basic astronomy.

To calculate 25% of 200, you multiply 200 by 0.25, which equals 50. This demonstrates the application of basic percentage calculations.

A liquid maintains a consistent volume but conforms to the shape of its container. This contrasts with solids, which retain both shape and volume, and gases, which take the shape and volume of their container.

Direct quotes provide concrete evidence of a character's actions and personality. They are essential for analyzing and supporting conclusions about character traits.

First, 9 multiplied by 8 equals 72, and then subtracting 10 results in 62. This question reinforces operations with multiplication and subtraction in the proper order.

Plants use the process of photosynthesis to convert light energy into chemical energy, making them producers. This biological process is key to sustaining life as it provides energy at the base of the food chain.

Subtracting 7 from both sides of the equation simplifies it to x = 8. This basic algebra problem illustrates how to isolate a variable.

Context clues consist of words or phrases surrounding an unfamiliar term that help a reader infer its meaning. They are an important tool for enhancing reading comprehension and vocabulary.

Let the width be w and the length be 2w. Since the perimeter is calculated by 2(w + 2w) = 6w and is given as 36, w equals 6, making the length 12 and the area 6 x 12 = 72.

Deposition is the process in which a gas transforms directly into a solid without first becoming a liquid. This conversion is a key concept in understanding phase changes in matter.

Foreshadowing provides subtle hints about what will occur later in the narrative, building anticipation. This literary technique enhances the reader's experience and creates suspense.

Both the numerator and the denominator of 18/24 can be divided by 6, which simplifies the fraction to 3/4. This is the simplest form since no further division by a common factor is possible.

Earth's seasons are primarily caused by the tilt of its axis relative to its orbital plane, which leads to varying sun exposure throughout the year. This axial tilt, rather than the distance from the sun, is responsible for the cyclical changes in weather.