Please help:

Consider a 3-month put option. Suppose that the underlying stock price is $25, the strike $26, the interest rate is 5% p.a., stock volatility is 6% per month. Use the same data to answer questions

1. What is the level of annual volatility (compute)?
2. Define in your own words implied volatility.
3. How would you compute implied volatility? Explain (no need to compute).
4. What is the probability of stock price going down (Note: use annual volatility, number of steps in a tree is N=3)?]
5. Build the binomial tree for the underlying asset (stock). Note: the tree nodes can be edited. Show computations for first up and first down nodes.