Answer:
B I think
Step-by-step explanation:
Area of a circle: πr²
Data:
diameter: 21 cm
radius=diameter/2=21 cm/2=10.5 cm
area of this circle: π(10.5 cm)²=110.25π cm² (≈346.36 cm²)
Answer: area=110.25π cm²
Using it's concept, the probability of choosing a number that is a multiple of 9 is of 0.111.
<h3>What is a probability?</h3>
A probability is given by the <u>number of desired outcomes divided by the number of total outcomes</u>.
From 1 to 81, there are 81 numbers, of which 81/9 = 9 are multiples of 9, hence, considering that 81 is the number of total outcomes and that 9 is the number of desired outcomes, the probability is given the following division:
p = 9/81 = 1/9 = 0.111.
More can be learned about probabilities at brainly.com/question/14398287
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Answer:
False
Step-by-step explanation:
Angles a and b add to 180° (linear pair), so angle b is 68°.
Answer:
-1/16
Step-by-step explanation:
Put the values where the variables are and do the arithmetic.
1 to any power is 1, so you can ignore all of the 'a' factors. That leaves ...
1/(2b^3) = 1/(2(-2)^3) = 1/(2(-8)) = -1/16
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A calculator can help you figure this out.