Suppose that alice and bob use the following protocol to check if they store the same secret. 1. alice generates a random n-bit value r. 2. alice computes x = ka ⊕ r, and sends x to bob. 3. bob computes y = kb ⊕ x and sends y to alice. 4. alice compares r and y. if r = y , she concludes that ka = kb—that is, alice and bob share a secret key. does the above protocol satisfy the two security properties identified in question (1)?