Answer:
Tâ = 16.7  °C
Explanation:
Given data:
Initial volume = 150.0 mL
Temperature = 25.0 °C
Final volume = 100 mL
Final temperature = ?
Solution:
Vâ /Tâ = Vâ/Tâ
Tâ = Vâ . Tâ/Vâ
Tâ = 100 mL .25 °C / 150.0 mL
Tâ = 2500 mL.  °C / 150.0 mL
Tâ = 16.7  °C