The temperature reading that is halfway between -10 degrees and 40 degrees is __degrees.
If the temperature was -3 degrees in the morning and 8 degrees in the afternoon, the change in temperature during that time is __ degrees.
If the temperature has been changing at a rate of -1.5 degrees each hour, and it is currently 5 degrees, the temperature 4 hours ago was __ degrees.
If the temperature continues to change at this rate of -1.5 per hour, and it is currently 5 degrees, the temperature in 4 hours will be __ degrees.