Question $6$ of $15.$In February $2021,$ Olivia paid $$4,500$ to acquire $150$ shares of DEF stock. In December $2023,$ DEF declared a two$-$for$-$one stock split. If there were no subsequent adjustments, what is Olivia's current basis in the stock, and how many shares does she own? $$2,250$ basis; $150$ shares. $$2,250$ basis; $300$ shares. $$4,500$ basis; $300$ shares. $$9,000$ basis; $150$ shares.