Biology & Astronomy - Questions, not Answers

Alright. Two things being tossed off my mind here.

1) Why February?

So when the calender was first made (gregorian), the months were given days according to the motion of the moon. Also, it was noted that a year is about 365.25 days, so a leap year was added every four years to negligate the approximation of 365.

However, it was noted that the days in one month had to be truncated to fit in 365. And then they truncated them from Feb. And now we can't rely on the day of the month to find the location of the moon.

But why were these days removed only from Feb? Why weren't the number of days in every month made equal?

2) Negative Half-Life?

Although a half life is negative, as in it is for decomposition, is there anything opposite to the phenomenon of exponential decomposition?

Take the example of Cancer cells. They divide, then the two cells again divide etc. The rate of reproduction increases over time. My question is, is there an accurate exponential formula for this? There really should be, according to physics, but there may be factors which inhibit the reproduction of a particular daughter cell of a cancereous parent...

3) Time travel

You will just have to wait for the release of my book.