Genie sends a letter in the U$.$S$.$ Mail offering to sell Kevin her rare box turtle for $\backslash (\backslash$$ $50\backslash ).$ Genie's offer states, "you must respond by mail if you wish to accept, your acceptance must be received by March $20$th$."$ Kevin sends his acceptance by mail on March $15$th$.$ Through no fault on Kevin's or Genie's part, the letter from Kevin is not delivered to Genie until March $25$th$.$ Genie now refuses to sell the turtle to Kevin, and Kevin has sued Genie for breach of contract. Under these facts, Kevin should: