A ____ is a list in which each element contains a key, such that the key in the element at position k in the list is at least as large as the key in the element at position 2k + 1 (if it exists) and 2k + 2 (if it exists).

Which of the following is valid?

a. float y; y = 54.9; b. float y; double z; z = 934.21; y = z; c. float w; w = 1.0f; d. float v; v = 1.0

_____________ describes the awareness that biometric sampling and identification is occurring.

Fill in the blank(s) with the appropriate word(s).