Answer:
reflexive property
Step-by-step explanation:
reflexive property states that a number equals itself, a = a, so since 16 = 16, or 16 equals itself, it's reflexive.
1.37 * 10^10 years.
Billion = 9 zeroes
13.7 billion = 13.7 * 10^9 = 1.37 * 10^10.
-18
Essentially the same as (-6) - 12
