救命！

1.VAR[S] = E[s^2] - (E[S])^2, using Ito to calculate S^2；
2.要用条件期望，E[S(t+h) / S(t)] = E[E[S(t+h) / S(t)|Ft]], 然后仿照上面的思路。注意，S(t) * f(t)将变成一个martingale，f(t)很容易得到，应用f(t)可以简化计算

From d(e^{\delta t} S_t), you can find S_t. Then, using ito's isometry to find the variance, and the conditional expectation to solve the second.

If needed, I can provide a more detailed solution. Please let me know.