models and simulations are useful because they allow us to study phenomena that are otherwise too small, too far away, or too complicated to observe. few models can replicate the actual phenomenon perfectly, however. Identify and explain one limitation of "Beyond the Black Hole"

what questions are you talking about ?

answer: d. load

a river's load refers to the natural phenomena in which the sediments, rocks   stones, boulders and other deposits are removed and picked from the bottom bed of the river due to the abrasion resulted by the high speed water current.