Hello cans someone explain how to answer these questions and the reasoning. thanks so much!Attachment 1Attachment 2uppwelling boxcoastNO_surfUArea =50km x 500kmthermoclineUNO deepFigure 2. Schematic of the box-model of the upwelling region.U: transport of water into and out of the box (m3 s-1)./7: export of organic matter out of the box as sinking particles (mol s-1).NO3deep: deep nitrate (for the water upwelling into the box) (mmol m-3).NO3surf: nitrate in the box (mmol m-3).