1) Thomas and Julie wanted to find out which material would insulate their teacher's coffee cup and keep the coffee hot for the longest period of time. They first wrapped her cup with bubble wrap and recorded the temperature of the coffee once every 15 minutes for 2 hours. They repeated the investigation, this time using newspaper instead of bubble wrap, but they got the same results for both materials.
What could they do to make sure their results are valid?
Repeat their experiment.
Use teas instead of coffee.
Use a different thermometer.
Conduct their investigation in a colder room.