A thermometer is taken from a room where the temperature is 18oC to the outdoors, where the temperature is −4oC. After one minute the thermometer reads 7oC. (a) What will the reading on the thermometer be after 4 more minutes? , (b) When will the thermometer read −3oC? minutes after it was taken to the outdoors?

Answer:(a) -37°C(b) 1[tex]\frac{10}{11}[/tex]minutes≈1.91 minutesStep-by-step explanation:(a) The thermometer reading was 18°C in a room and this dropped to a reading of 7°C outdoor after 1 minute hence in 1 minute, temperature (heat) loss= [tex]18-7[/tex]=[tex]11[/tex]°CAfter 4 more minutes, the thermometer would have lost additional 44 minutes (4×11). Hence thermometer reading after 4 more minutes would be[tex]= 18 - 11 - 44        = -37°C(b) The thermometer loses temperature at 11°C per minute. For the thermometer to read -3°C, the temperature loss must be= 18-(-3)= 21°CAt a temperature loss rate of 11°C, the thermometer would lose 21°C in=[tex]\frac{21}{11}[/tex]=1[tex]\frac{10}{11}[/tex] minutes≈1.91 minutes