Final answer:
To bake a cake with a flat top for decoration, reduce the oven temperature by 25°F compared to the recipe's guidelines, especially important in higher altitudes where cooking times may vary due to changes in the boiling point of water.
Step-by-step explanation:
To ensure that the cake you are baking has a flat top suitable for decoration, you should reduce the temperature by 25°F. Baking at a lower temperature allows the cake to rise more evenly because the edges do not set too quickly before the middle has a chance to rise. Consequently, this helps to prevent a dome from forming on the top of your cake. Remember that typical kitchen appliances such as ovens are calibrated using the Fahrenheit scale, so if you're in the United States, recipes and adjustments are generally provided in Fahrenheit. Additionally, if you're living at a higher altitude, it's important to be aware that cooking times may be longer since water boils at a lower temperature as elevation increases.
For those in Europe, conversions to Celsius and Kelvin would be necessary for your oven settings. For example, if you need an oven temperature of 450°F, you would find the Celsius equivalent is about 232°C and the Kelvin temperature is approximately 505°K.