The Pythagorean theorem states that the square of the hypotenuse is equal to the sum of the squares of the legs:

The hypotenuse is the side with the greatest length.
Check all options:
1. c=5, a=3, b=4:
true.
2. c=14, a=4, b=11:
false.
3. c=17, a=9, b=14:
false.
4. c=16, a=8, b=14:
false.
5. c=17, a=8, b=15:
true.
Answer: correct options are A and E.
The Neolithic Revolution allowed people to live in permanent settlements.
<u>Explanation:</u>
The Neolithic Revolution is the phase of transition in which many of the human cultures in the world shifted their lifestyle to permanent settlement and agriculture from hunting and gathering.
This era is also named as First Agricultural Revolution or Neolithic Demographic Transition. The agricultural practices led the cultures to develop the knowledge of domestication of animals and they began to observe and experiment with the plants (to learn or know how they grow and develop).
Neolithic period is named as revolution because this period changed the way of life of most of the communities. This first occurred in so-called "Fertile Crescent" or Mesopotamia (modern Iraq).
Answer:
1. y ≥ 100
2. y ≤ 300
3. y ≥ 20000
4. 2y ≥ 80
5. 2y ≤ 90
Step-by-step explanation:
Let y be the variable.
1. The discount is not less than 100.
If the discount (i.e y) is not less than 100, it means it is either 100 or greater than 100.
This can be written as:
y ≥ 100
2. The cost of the book is at most 300.
This implies that the cost of the book (i.e y) is either 300 or lesser.
This can be written as:
y ≤ 300
3. His monthly income is at least 20000. This simply means that his monthly income (i.e y) is 20000 or greater than 20000.
This can be written as:
y ≥ 20000
4. Twice the number is at least 80.
Let the number be y.
Twice the number y can be written as:
2y
But twice the number is at least 80.
This means that twice the number is 80 or greater than 80. This can be written as:
2y ≥ 80
5. Twice the measure of the acute angle is not more than 90 degree.
Let the angle be y.
Twice the angle can be written as:
2y
But twice the measure of the angle is not more than 90 degree. This implies that twice the angle is 90 or lesser than 90. This can be written as:
2y ≤ 90
Answer:
1. CYNARG
Step-by-step explanation:
This a example of Caesar's Cipher, in which each letter in the original word leads to a ciphered letter according to the following equation:

In which C is the index of the Ciphered letter in the alphabet, P is the index of the original letter and o is the offset.
Finding the offset:
O is coded B
O is the 15th letter in the alphabet, so
.
B is the 2nd letter in the alphabet, so 




So

PLANET:
P
P is the 16th letter in the alphabet.

So P is coded C.
L
L is the 12th letter in the alphabet:

L is coded Y(25th letter in the alphabet)
A
A is the 1st letter in the alphabet

A is coded N
N
N is the 14th letter in the alphabet

N is coded A
E
E is the 5th letter in the alphabet

E is coded R
So the correct answer is:
1. CYNARG