Answer: 
Step-by-step explanation:
For convenience, I labeled some points as shown in the attached picture.
Also, I assume 
and 
are tangents to the circle.
(reflexive property)
(tangents drawn from a common external point are congruent)
(right angles are congruent)
Therefore, we know 
by HL.
Thus, by CPCTC,
This means the measure of minor arc AC is 
, and thus 
Answer: 0.4 which is choice C
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Work Shown
Focus on the "riverside high school" row only
A = number of twelfth graders = 200
B = number of students = 500
P = probability of picking a twelfth grader
P = A/B
P = 200/500
P = 2/5
P = 0.4
Answer:
we can conclude that there is no significant evidence to conclude that the mean score in 2010 differs from the mean score in 2009.
Step-by-step explanation:
H0 : μ = 582
H1 : μ < 582
Test statistic :
T = (xbar - μ) ÷ σ/√n
Xbar = 515 ; n = 20 ; σ = 120
T = (515 - 582) ÷ 120/√20
T = -67 / 26.832815
T = 2.50
Pvalue at t score = 2.50 ; df = 19 is 0.0187
At α = 0.0187
Pvalue > α ; Hence, we fail to reject the Null
Hence, we can conclude that there is no significant evidence to conclude that the mean score in 2010 differs from the mean score in 2009.
Probability of divisibility by3=4/11
probability of divisibility by 12 =1/11
probability of divisibility by 12 and 3=4/11×1/11
answer is 4/121
