The answer is 2- circulatory and excretory
Answer:
if you are asking about the types of blood the there is O, A, B, and AB together
Explanation:
The answer is FR schedule or fixed ratio schedule. It is a timetable of fortification where a reaction is strengthened simply after a predefined number of reactions. Basically, the subject gives a set number of reactions and after that, the mentor offers a reward. One preferred standpoint of this kind of calendar is that it creates a high, enduring rate of reacting with just a concise delay after the conveyance of the reinforcer.
