Answer: b) 84
Step-by-step explanation:
Let p be the prior estimate of the required proportion.
As per given , we have
p =0.5 (The probability of getting heads on a fair coin is 0.5)
Significance level : 
Critical z-value (using z-value table ) : 
Confidence interval width : w= 0.18
Thus , the margin of error : 
Formula to find the sample size ( if prior estimate of proportion is known.):-

Substitute the values , we get

Simplify ,
[Round of to the next whole number.]
Hence, the number of times we would have to flip the coin =<u>84</u>
hence, the correct answer is b) 84
Your question is incomplete can you please elaborate so I can assist you? :)
A.0 I think ................
90 days.
For this question you just need to find the least common multiple of 18 and 30. That can be found by first finding the prime factorization of each number. 18 = 2 * 3 * 3 and 30 = 2 * 3 * 5. Then you multiply the 2 * 3 * 3 * 5, you ignore the 3 from 30 because 18 has more 3s. The answer is 90.
Answer: 135, 45, and 135 are the three other angles
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Explanation:
For a parallelogram, we'll have opposite angles with the same measure. So if one angle is 45 degrees, then the opposite angle is also 45 degrees. The other two angles are 180-45 = 135 degrees each. Adjacent angles in a parallelogram add to 180 degrees.