Area = π x radius²
dA/dr = 2πr
Average rate of change = (rate of change at one instant + rate of change at other instant)/2
= (2πr₁ + 2πr₂)/2
= (r₁ + r₂)π
Ai) 9π
Aii) 8.5π
Aiii) 8.1π
B) Instantaneous change:
(dA/dr) at (r = 4) = 2π(4)
= 8π
Divied 4 by both 180 and 320 because 4 quarters= a dollar
$26.98 x .20=5.396 tip.
So, depending if if you need to round to the nearest cent, the tip would be $5.40 + bill $26.98=$32.38 total amount.
If you are rounding to the nearest dollar, the tip would be $6+26.98= $32.98.
Answer:
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Step-by-step explanation:
