I'm assuming this question is about snakes and not poultry?
The reason snake eggs take a while to hatch is to accomodate for development of the emrbyo. When an egg is first laid there is no developed snake embryo inside, it will take a while to develop and will not hatch until development is complete. Variations in temperature, humidity, ect. can effect the rate of development and cause variation in the actual date of hatch.
Alligators have a gestation period of 60-65 days.
50-65 days
Depending on the specie, will determine the incubation period. Species in smaller size will usually have a smaller egg, which will have a shorter incubation period than a larger specie. Typically eggs will take 40-120 days in most common gecko species.
It will take 65/50 = 1.3 hours = 1 hour 18 minutes.
65 days
50% of 65 = 50% * 65 = 0.5 * 65 = 32.5
To be accurate here, we take 365.25 days in a year, /12, x6.5 is 197.84 days, round to 198 days
65 days
60 - 65 days
63-65 days
37.7 C is optimum. No more than 38.6 or the hatch will be reduced greatly. Optimum humidity is 65% for the first 18 days with an increase to 85% for the final three days.
65% of 50= 65% * 50= 0.65 * 50= 32.5