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

5 0

3 years ago

The profit at a factory that makes CD's can be computed using the linear equation p = 2.5d - 1000 where p is the profit and d is

telo118 [61]

The slope is 2.5/1 such that 2.5 rise and 1 is run.

It represents the number of CD's.

8 0

4 years ago

Read 2 more answers

Last week, the daily low temperatures for a city, in degrees Celsius, were 5, 8, 6, 5, 10, 7, and 1. What was the average low te

ludmilkaskok [199]

The average low temperature would be 5+8+6+5+10+7+1 all divided by 7, so the answer is 6° celsius.

3 0

3 years ago