The variable rate in a plain vanilla swap agreement is usually the

a$.$Fed funds rate

b$.$Libor rate

c$.$Swap rate

dDiscount rate

$1.$ An equity swap is an agreement to

a$)$ Exchange returns on a specified equity or equity index periodically for a specified stream of returns such as Libor interest payments.

$($b$)($b$)$ Exchange returns on a specified equity or equity index periodically for a specified stream of returns from another equity or equity index dominated in a foreign currency.

$($c$)($c$)$ Exchange returns on a specified equity or equity index periodically for a specified stream of returns such the return on another equity or equity index denominated in the same currency.

$($d$)($d$)$ a and c only