Answer:
its d i think bc i had that on my quizz
Step-by-step explanation:
Answer:
72
Step-by-step explanation:
Answer:
Answer is A
Step-by-step explanation:
It's closed under addition. You can take any two natural numbers you want, add them up and you'll get some other natural number (eg: 3 and 5 ---> 3+5 = 8)
it's not closed under subtraction. Sure 5-3 = 2 is a natural number but 3-5 = -2 is not a natural number
so that leads us to the answer being choice B