G, P and S are animal species. What is the average life span in years of S?
I. The average life span of S is twice that of P and $$\frac{4}{5}$$ that of G.  
II. The average life span of G is 30 yr longer than that of P and 10 yr longer than that of S

if Statement I alone is sufficient but Statement II alone is not sufficient to answer the question

if Statement II alone is sufficient but Statement I alone is not sufficient to answer the question

if both statements taken together are sufficient to answer the question but neither Statement alone is sufficient

if Statements I and II together are not sufficient, and additional data is needed to answer the question