Implied Question: Even though one cannot generally know the exact fortieth day of the baby's formation ...

Reason: Seeing as the semen can delay taking root until the third day ...

Answer: Nevertheless, Shmuel was an expert ...

Clarification: It is possible for the womb to open without blood ...

Halachah: And this is how the She'iltos of Rav Acha'i Gaon Paskens ...

Source: Based on the current Sugya - from the fact that one can Shecht and sprinkle the blood for her.

Question #1: The Gemara in Perek Eizehu Mekoman (Zevachim, Daf 48a) states that one may bring a Chatas that is worth a Danka (a sixth of a Dinar).

Question #2: Furthermore, the Gemara later (on Daf 27a) Explains that the Torah did not specify a fixed amount for Mechusrei Kaparah - in case the value of lambs drops and they will not be able to obtain a Kaparaha?

Answer: When the Gemara talks of 'a lamb for a Sela', it was customary to purchase it at that price in order to perform the Mitzvah in an ideal fashion , but one was permitted to spend less.

Asham: An Asham on the other hand, had to be worth two Shekalim, since it is d'Oraysa ...

Chatas: Whereas a Chatas has no Shi'ur min ha'Torah, only mi'de'Rabanan ...

Chatas (cont.): Therefore Lechatchilah, one should spend a Sela, and Bedi'eved, a Danka, but for less than that, one is called 'Avaryana' (a sinner).

Chatas (concl.): Nevertheless, in the event that the price drops, and there are fat sheep that are worth les than a Danka, one attains one's atonement with them.

Asham (cont): But Ashamos, even if the rams are fat and good, if they are worth less two Shekalim, due to a drop in price, one does not attain atonement ...

Reason: Since the Torah writes "Kesef Shekalim".