Answer:
0.6 °C/min
Step-by-step explanation:
The relationship between rates and movement is ...
time = distance/speed
Here, the "distance" is measured in °C, and the "speed" is the rate of change of temperature.
For the first half of the heating, the time required is ...
(50°C -0°C)/(1.5 °C/min) = 50/(3/2) min = 100/3 min
For the second half of the heating, the time required is ...
(100°C -50°C)/(4/10 °C/min) = 50/(4/10) = 125 min
Then the total time is ...
((100/3) +125) min = (475/3) min
And the average rate of temperature increase is ...
total temperature change / total time
= (100°C -0°C)/(475/3 min) = 300/475 °C/min = 12/19 °C/min ≈ 0.6 °C/min