Hi
679.99728885721s is the time it takes for the missile to reach the harvester position minus the time it takes the harvester to escape, so the time during which it can safely harvest.
33.978933061502s is the time it takes that harvester to lift a single cow from the ground based on it’s efficiency.
Thank you, this helped me reverse-engineer the computations to make, which helped me understand parts of the statement retroactivaly 
I might have missed something but I tend to get +1 cow on the expected result time to time and can’t get why…
If I understood well, missile always starts from 46m elevation and reachs 160 000m elevation. Collector hovers at base elevation + 500m, so need time to reach 160 000m from this point to escape. Am I correct for this part ?
For example, in test case 1 : I get 16 cows saved on Working Cows Dairy instead of 15
Your understanding is correct, if by “base elevation” you meant the elevation of the mission location.