1. \( 2.4 \mathrm{~km}=\square \mathrm{cm} \)

To convert kilometers to centimeters, remember that 1 kilometer equals 100,000 centimeters. So, multiplying 2.4 km by 100,000 gives us \( 2.4 \times 100,000 = 240,000 \) cm. Thus, \( 2.4 \mathrm{~km} = 240,000 \mathrm{~cm} \)! It's like converting a long road trip into tiny steps! When working with unit conversions, it’s helpful to write down conversion factors. This visual aid can prevent mistakes, like mixing up kilometers with meters or centimeters. Always carefully double-check your multiplication and make sure you’re using the right units. Happy converting!