R. Yehudah says, blood is not Mevatel blood.

If it became mixed with blood of Pasul Korbanos, all the blood is poured into the Amah (a stream that flowed out of the Mikdash). If it became mixed with Tamtzis blood, all is poured into the Amah;

R. Eliezer is Machshir (to do Zerikah).

If the Kohen did not ask the Halachah and did Zerikah, it is Kosher.

(Gemara - R. Chiya bar Aba): The case is, water fell into blood, but if blood fell into water, each drop becomes Batel when it falls in (and even when the mixture has the appearance of blood, it is Pasul for Zerikah).

(Rav Papa): The law is different regarding Kisuy (covering the blood of a slaughtered bird or Chayah), for Mitzvos are not Nidchim. (Even if blood fell into water, if it looks like blood, the Mitzvah applies.)

(Reish Lakish): If one ate Pigul and Nosar (and Tamei - this is not in Rashi's or Tosfos' text) that were mixed together, he is exempt. Surely, (they were not exactly equal,) one of them was the majority, the other is Batel. (He cannot be lashed for either, perhaps it was Batel.)

We learn three things from this;

Different Isurim (forbidden things) can be Mevatel each other;

If an Isur gives taste to a food of a larger volume than itself, it does not forbid it (to obligate lashes) mid'Oraisa (Reish Lakish's law applies even when the minority gives taste),

Hasra'as Safek (a warning not to transgress when it is not clear if the action about to be done transgresses the Lav) is not proper warning. (The first opinion in Tosfos - the case is, he ate two pieces. One of them was mostly Pigul, and the other was mostly Nosar, andwe do not know which was which. He was warned each time not to eat Pigul. Since we do not know which time he ate Pigul, he is exempt. The second opinion says that in such a case he would be liable (Tzon Kodoshim); rather, (we explain this opinion according to Panim Me'iros) both pieces were mostly Pigul, or both were mostly Nosar, and we do not know which. The first time he was warned not to eat Pigul, and the second time, not to eat Nosar, which implicitly cancels the warning for Pigul). Since we do not know which warning he transgressed, he is exempt.)

Question (Rava - Mishnah): If a dough was made with wheat flour and rice flour:

If the wheat can be tasted, Chalah must be taken, even if the rice is the majority.

Answer #1: That is mid'Rabanan. Mid'Oraisa it is exempt.

Rejection (Seifa): (If it was baked into Matzos for the sake of Pesach), one is Yotzei with it. (This shows that mid'Oraisa, the wheat is not Batel, because it can be tasted!)

Answer #2: Rather, Min b'Eino Mino (when different foods are mixed), if the minority gives taste, it is not Batel;

Min b'Mino (when identical foods of different Halachic status are mixed), the minority is Batel to the majority. (Reish Lakish discussed this case. We cannot infer the law of Min b'Eino Mino.)

Question: Also Min b'Mino, the minority should not be Batel if it is enough that if it was Eino Mino, it would give taste!

(Mishnah): If blood became mixed with wine (which has the same appearance), we consider it to be like water.

Suggestion: This means, we consider the wine to be like water (we may do Zerikah only if the appearance would be like blood).

Answer #1: No, it means, we consider the blood to be like water (if it is the minority, it is Pasul for Zerikah).

Objection #1: If so, it should simply say that it is Pasul!

Objection #2 (Beraisa - R. Yehudah): (If a Tamei bucket with (but not full of) white wine was immersed in a Mikvah (the remainder of the bucket fills up with water), we consider the wine to be red:

If the appearance (of red wine) would become faint (cease to resemble wine) when mixed with this ratio of water, the immersion is valid (the wine became Batel to the water). If not, the immersion is Pasul.

Answer #2: Tana'im argue about whether we consider Min b'Mino like Min b'Eino Mino (and Reish Lakish holds like Chachamim):

(Beraisa): (If a bucket of white wine or milk was immersed) we follow the majority (the immersion is Kosher only if the majority is water);

R. Yehudah says, we consider the wine to be red. If the appearance would become faint, the immersion is valid; if not, it is not.

Contradiction (Mishnah): If a bucket full of spit was immersed, the immersion is invalid (the water does not penetrate to reach the interior);

Version #1 (our text, Rashi): If the bucket contains urine, we consider it like water (for urine is a kind of water. The immersion is valid);

Version #2 (Tosfos): If it contains urine, we consider it like wine. If it would become faint, the immersion is valid; (end of Version #2)

If it contains Mei Chatas, it is valid only if the water is the majority.

Version #1 (Rashi) Summation of contradiction: This is like R. Yehudah (who considers things (e.g. urine) to have different appearances, yet a majority suffices regarding Mei Chatas. We do not view it like wine!

Version #2 (Tosfos) Summation of contradiction: This is like R. Yehudah (in cases of Min b'Eino Mino of similar appearances (e.g. urine in water), he considers it to have a different appearance), yet Mei Chatas is Batel in a majority of water, whereas in the Mishnah, R. Yehudah said that Min b'Mino is never Batel!