$\backslash$Between January $2022$and June $2022,$the market price of Brent crude oil increased from

approximately $$80$per barrel to approximately $$120$per barrel. The oil price subsequently

fell back to approximately $$80$per barrel by the end of the year.

$($a$)$Present a fully$-$labelled diagram to show how this scenario can be depicted in the

Dynamic Model of Economic Fluctuations

$.$Assume that this situation can be modelled as a persistent supply

shock which hits firms$$input costs for two quarterly time periods $($t and t$+1)$and

disappears thereafter. Further assume that the economy begins and ends in a

long$-$run equilibrium position