Answer:
i. 9
ii. 14
iii. 405
iv. 
Step-by-step explanation:
The number of diagonals in a polygon of n sides can be determined by:

where n is the number of its sides.
i. For a hexagon which has 6 sides,
number of diagonals = 
= 
= 9
The number of diagonals in a hexagon is 9.
ii. For a heptagon which has 7 sides,
number of diagonals = 
= 
= 14
The number of diagonals in a heptagon is 14.
iii. For a 30-gon;
number of diagonals = 
= 
= 405
The number of diagonals in a 30-gon is 405.
iv. For a n-gon,
number of diagonals = 
The number of diagonals in a n-gon is 
Answer: After working for 33
hours a week
Step-by-step explanation:
Let us write equations to represent these two places. Let x be hours worked and y be money earned.
Tim Hortons:
$200 + $5x = y
McDonalds:
$300 + $2x = y
Now, to find the conditions of which Tim Hortons is the better employer (on the basis of money earned) we must find the interval that Tim Hortons pays more. This can be found by setting up another equation, or by graphing. I have shown both. <em>See attached for the graph</em>.
$200 + $5x > $300 + $2x
$5x > $100 + $2x
$3x > $100
x > 
x > 33.3334
Tim Hortons is the better employer after an employee has worked for 33
hours a week.
<em>Read more about </em><em>this question</em><em> here:</em>
<em>brainly.com/question/24206551</em>
C. Phonograph were inferior in sound quality.
Step-by-step explanation:
Researches have shown that plants respond to the sounds of their pollinator.
Some plants begin to produce a greater amount of nectar and some begin to vibrate to attract the attention of the pollinators towards them.
Greater the intensity of the sound of the pollinator, the faster the reaction will be.
Phonographs have a sound of lower intensity when compared to the intensity of sound produced by the radio.
Thus the radio was better than the phonograph in encouraging the concept of cross-pollination.
Let x represent the amount of months she has been saving for.
20x - 60 = 280
Solve for x.
20x - 60 = 280
~Add 60 to both sides
20x - 60 + 60 = 280 + 60
~Simplify
20x = 340
~Divide 20 to both sides
20x/20 = 340/20
~Simplify
x = 17
Therefore, Melanie has saved for 17 months.
Best of Luck!
Answer:
-250
Step-by-step explanation:
I don't know for sure but I hope it's correct.