Natural numbers are closed under division: false.
A set is closed under a certain operation if the results of that operation are always inside that set.
So, if natural numbers were closed under division, the division of two natural numbers would always be a natural number.
You have plenty of counterexamples, to pick one you may divide any odd number by 2: 5/2 is not a natural number.
Negative numbers are closed under addition: true.
Let 
be two positive numbers. So, 
are two negative numbers. Their sum is
And since 
is positive, we deduce that 
is negative, so the sum of two negative numbers is still negative.
Prime numbers are closed under subtraction: false.
This would mean that the subtraction of two primes is also a prime. Again, there are many counterexamples: 7 is prime and so is 3, but their difference 7-3 is 4, which is not prime.
(C) "serpentine"
Serpentine is a winding word. The phrase would read "The mountain road was distinctly serpentine: it twisted back and forth along the contours of the hillside" if this term were added to the text.
The comma denotes that the meaning of the omitted phrase will be clarified in the second clause of the sentence. Because a winding road does actually curve "back and forth," the word "serpentine" matches the text. The answer is not (A).
A panoramic view is one that encompasses the entire surrounding region. (B) is the wrong answer. Precipitous refers to a steep slope. The answer is not (D). The term "circumscribed" describes something that is restrained or encircled by a line. The answer is not (E). Moving backward is referred to as retrograding.
Here's another question with an answer similar to this about passage analysis: brainly.com/question/3521530
#SPJ4
1) The triangles are congruent by SSS.
The two tick marks indicate two pairs of congruent sides; it is evident that the third side is congruent by the way the diagram is drawn - the bases of the triangles are together and appear to be the same length.
2) The triangles are congruent by SAS.
The two pairs of tick marks indicate congruent sides, and their included angles are congruent because they are vertical angles, and vertical angles are always congruent.
To find how much is 48% of 50:
(48 x 50) / 100
2,400 / 100
24 goals where scored by Eileen.
Hope it helped,
Happy homework/ study/ exam!
Answer:
3.5 in²
Step-by-step explanation:
Given:
Radius (r) = 1.5 in.
Formula for area of half circle = (πr²)/2
Required:
Area of the half circle
Solution:
Plug in the values into the formula for area of half circle.
Thus:
Area = (π × 1.5²)2
= 7.06858347/2
Area = 3.5 in² (nearest tenth)
