a) Name the hormones secreted and write their functions:
i) by corpus luteum and placenta (any two).
ii) During Follicular phase and parturition.
b) Name the stages in a human female where:
i) Corpus luteum and placenta co-exist.
ii) Corpus luteum temporarily ceases to exist.

Explanation

### Step-by-Step Solution:

**a) Name the hormones secreted and write their functions:**

**i) By Corpus Luteum and Placenta:**

1. **Corpus Luteum:**
- **Hormones Secreted:**
...