Y = yo + Vot - (gt^2)/2
0 = 0 + 31t - 4.9 t^2
0 = -4.9 t^2 + 31t
Answer: option A.
Sum of all the interior angles = (5-2)x180 = 540°
540 - 100 - 120 - 100 - 90 = 130°
So the last unknown angle in the polygon is 130°
Sum of all the adjacent angles on a straight line is 180°
Angle 1 = 180 - 130 = 50°
Answer:
Step-by-step explanation:
Since the sample size is quite large, we can use the z-distribution.
The margin of error is given by
Where n is the sample size, s is the sample standard deviation and 
is the z-score corresponding to a 90% confidence level.
The z-score corresponding to a 90% confidence level is
Significance level = α = 1 - 0.90= 0.10/2 = 0.05
From the z-table at α = 0.05
z-score = 1.645
Therefore, the margin of error is 0.776.
Given:
n = 27, sample size
df = n-1 = 26, degrees of freedom
xb = 11.8, sample mean
s = 2.3, sample standard deviation.
Because population statistics are not known, we should use the Student's t-distribution.
At 99% confidence interval, the t-value = 2.779 (from tables).
The confidence interval is
11.8 +/- 2.779*(2.3/√(27)) = 11.8 +/- 1.23 = (10.57, 13.03)
Answer: (10.6, 13.0) to the nearest tenth
