Consider the following spot interest rates for maturities of one, two, three, and four years.

r$1=4\mathrm{.}1\%$

r$2=4\mathrm{.}9\%$

r$3=5\mathrm{.}6\%$

r$4=6\mathrm{.}5\%$

What are the following forward rates, where fk$,1$ refers to a forward rate beginning in k years and extending for $1$ year?

a$).$ f$2,1=?$

b$).$ f$3,1=?$

$($Note: Express your answer in percentages; round your answer to four decimal places.$)$

Hint: Use the equation $(1+$ rk$)$k $\backslash$times $(1+$fk$,1)=(1+$ rk$+1)$k$+1$ to solve for fk$,1.$