$\backslash$table$[[$Date$,$Activities,Units Acquired at Cost,Units Sold at Retail$],[$August $2,$Purchase,$10$ units @ $$12=$$$120,],[$August $18,$Purchase,$15$ units @ $$15=$$$225,20$ units sold$],[$August $29,$Sales,,$]]$

What is the per unit value of ending inventory on August $31?$ Answers should be rounded to the nearest cent.

Multiple Choice

$$12\mathrm{.}00$

$$13\mathrm{.}80$

$$15\mathrm{.}42$

$$16\mathrm{.}00$

$$17\mathrm{.}74$