Question

gary drinks coffee with milk every morning. he notices that some mornings his coffee seems to cool down quickly and some mornings it seems to stay warm longer. he wonders what factors affect how quickly his coffee cools down. he has the following supplies available: two small coffee mugs, two large coffee mugs, hot caffeinated coffee, a pot, a stove, cold milk, a thermometer. using only these supplies, which questions can gary investigate with an experiment? select all that apply. does a small mug of coffee stay warm longer than a large mug of coffee? does a large mug of coffee stay warm longer when warm milk is added instead of cold milk? does a small mug of coffee cool down more quickly if it is sweetened with sugar or if it is unsweetened? does a small mug of coffee stay warm longer when warm milk is added instead of cold milk?

Explanation:

Step1: Check available supplies

Gary has small and large coffee mugs, hot coffee, cold milk, a pot, a stove and a thermometer.

Step2: Analyze each question

For the question about mug - size, he can use the mugs and thermometer. For questions about milk - temperature, he has cold milk and can heat milk on the stove and use the thermometer. Since there is no sugar among supplies, he cannot test the effect of sugar on cooling.

Answer:

1. Does a small mug of coffee stay warm longer than a large mug of coffee? - Yes
2. Does a large mug of coffee stay warm longer when warm milk is added instead of cold milk? - Yes
3. Does a small mug of coffee cool down more quickly if it is sweetened with sugar or if it is unsweetened? - No (sugar is not among the supplies)
4. Does a small mug of coffee stay warm longer when warm milk is added instead of cold milk? - Yes