After a lion made a kill, birds will sometimes arrive to pick at the leftover carcass. which are the predators: the birds, the lion, or both? why?

Both depending on what type of bird it is The lion is obliviously a predator but the bird (depending what type it is ) makes it some what of prey to And the bird is also a predator cause ya it eats meat for sure so that tells you automatically this little or big bird can obviously kill something but it can also be a prey to the lion if the male/female grabs it in time so they are both predators/prey .  

d

explanation:

the higher the instrument the better

it provides an alternative energy pathway for the reaction to proceed.

a catalyst is a substance that speeds up the rate of a chemical reaction but is not consumed during the course of the reaction.

catalysts increase the rate of reaction without being used up. they do this by lowering the activation energy needed. with a catalyst, more collisions result in a reaction, so the rate of reaction increases. different reactions need different catalysts.

a catalyst works by providing an alternative reaction pathway to the reaction product. the rate of the reaction is increased as this alternative route has a lower activation energy than the reaction route not mediated by the catalyst.