9 : 2 = 18 : 4
As: 9 x 2 : 2 x 2 = 18 : 4
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36 : 8 = 18 : 4
As: 18 x 2 : 4 x 2 = 36 : 8
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72 : 16 = 18 : 4
As: 18 x 4 : 4 x 4 = 72 : 16
Slope intercept form = Y = Mx + B
15 = -3y + 21x
3y = 21x - 15
Y = 21/3 X - 15/3
Y = 7x - 5 = SI Form
Answer: 8m^10n^10
Thats the answer i hope i was helpful!
First convert 4 cms to mms by multiplying by 10
then divide this by number of days in a year (365)
so R = 10*4 / 365
= 0.109589 mm / day