Fill in the blanks by choosing the appropriate word/words from those given in the bracket:
(vacant, square planar, tetrahedral, 64%, crystal, decreases, efficient, increases, 74%, `sp^(3)d^(2), sp^(3)`)
Noble gases have........ ionization enthalpy and more........ electron gain enthalpy. (high, positive)

Explanation

To solve the question, we need to fill in the blanks with the appropriate words from the options provided. The statement is: "Noble gases have ______ ionization enthalpy and more ______ electron gain enthalpy."

### Step-by-Step Solution:

1. **Understanding Noble Gases**:
- Noble gases are located in Group 18 of the periodic table. They include elements like helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn).
- They have a complete outer shell configuration, which is typically represented as ns²np⁶.

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