A thermometer is taken from a room where the temperature is 20oc to the outdoors, where the temperature is - 15oc. after one minute the thermometer reads 7oc. (a) what will the reading on the thermometer be after 5 more minutes?

To find the temperature after 5 minutes you will find the rate of change that occurred in the first minute and apply that to the next 5 minutes.

The temp drops 13 degrees (20-7) after 1 minute, so it will drop 13 more minutes the next minute (7-13 = - 6 degrees)

Another 13 the next minute (-6-13=-19), BUT it will not drop below the actual air temp.

The thermometer should be at - 15 degrees after 5 minutes.