1) D: The LD 50/60 for radiation is approximately 3.25 Gy. The GI syndrome is seen at exposures of 7-10 Gy and is invariably fatal, despite aggressive fluid therapy.   

The GI and Cerebrovascular Syndromes are invariably fatal.

2) B: Women 18-25 years old tend to recover fertility at doses below 4 to 5 Gy. Sterility is likely to be permanent at doses above 5 to10 Gy. The closer a woman is to menopause, the smaller the radiation dose necessary to induce sterilization.