🔍 Key Concepts

• thermal expansion of liquids such as fuel oil when heated • difference between volume, weight, and heat units (like BTUs) • basic definition of viscosity

💭 Think About

• Which choice actually describes a rate of volume change as temperature increases? • Do British Thermal Units (BTUs) measure how much something expands, or how much heat energy is added or removed? • Is viscosity (how thick a fluid is) the same thing as how much its volume increases when heated?

✅ Before You Answer

• Identify which option refers to a percentage change per degree of temperature rise (that matches a rate of expansion). • Eliminate any options that talk about units of heat or weight, since expansion here is about change in volume. • Confirm that viscosity describes resistance to flow, not how much volume changes with temperature.