$6)$ To perform deacylation assays in Figure $3,$ the authors created tRNA with a $32$P label in a two$-$step process starting with unlabeled tRNA. The following questions are about this process.

a$)$ In step $1,$ the unlabeled tRNA is incubated with pyrophosphate and CCA adding enzyme. Using the diagram below, use arrows to show the reaction that will be catalyzed between these two substrates, and draw the products that will result from the activity of CCA adding enzyme. All atoms that are shown explicitly in the starting diagram should be shown in your products in their correct chemical configuration. $(3$ points$)$

b$)$ In step $2,$ pyrophosphatase enzyme is added to the reaction to degrade remaining pyrophosphate from step $1$

and $\backslash$alpha $32$P ATP is added. Draw the products created by CCA adding enzyme under these conditions, and circle

the position of the labeled phosphate in the resulting tRNA. $(3$ points$)$

c$)$ Why does addition of pyrophosphatase enzyme promote accumulation of the labeled tRNA? $(1$ point$)$