Question $4[5$ points$].$

Let $T_0,$cdots,$T_n$ denote an initial time $T_0$ and a set of coupon payment dates. We write ${}_i=T_i-T_{i-1}$ for $i=1,$dots,$n.$ An interest rate cap on LIBOR with strike $K$ pays the holder ${}_i(L(T_{i-1},T_i)-K)$ if it is positive at $T_i$ otherwise nothing for $i=1,$dots,$n.$ An interest rate floor pays the holder ${}_i(K-L(T_{i-1},T_i))$ if it is positive at $T_i,$ otherwise nothing for $i=1,$dots,$n.$

$[3$ point