Farenheit is an interesting unit so the conversions get a bit weird.
To convert from Farenheit to Celcius you follow this formula:
T(°C) = (T(°F) - 32) × 5/9
It is also easier to convert to Celcius to Kelvin shown in this formula:
T(K) = T(°C) + 273.15
To Answer your question:
105° F = 40.5°C
-25° F = -31.7°C
105° F = 313.65K
-25° F = 241.45K