Answer:
m∠CFD is 70°
Step-by-step explanation:
In the rhombus
- Diagonals bisect the vertex angles
- Every two adjacent angles are supplementary (their sum 180°)
Let us solve the question
∵ CDEF is a rhombus
∵ ∠E and ∠F are adjacent angles
→ By using the second property above
∴ ∠E and ∠F are supplementary
∵ The sum of the measures of the supplementary angles is 180°
∴ m∠E + m∠F = 180°
∵ m∠E = 40°
∴ 40° + m∠F = 180°
→ Subtract 40 from both sides
∵ 40 - 40 + m∠F = 180 - 40
∴ m∠F = 140°
∵ FD is a diagonal of the rhombus
→ By using the first property above
∴ FD bisects ∠F
→ That means FD divides ∠F into 2 equal angles
∴ m∠CFD = m∠EFD = 
m∠F
∴ m∠CFD = (140°)
∴ m∠CFD = 70°
Answer:
Sample mean = 7.1
Margin of error = 0.465
Step-by-step explanation:
Formula for confidence interval is;
CI = x¯ ± zE
Where;
x¯ is sample mean
z is critical value at confidence level
E is margin of error.
z for 99% Cl is 2.58
We are told the CI is 5.9 to 8.3.
Thus;
5.9 = x¯ - 2.58E - - - - (1)
8.3 = x¯ + 2.58E - - - - (2)
Add both equations together to get;
14.2 = 2x¯
x¯ = 14.2/2
x¯ = 7.1
Put 7.1 for x¯ in eq 1 to get;
5.9 = 7.1 - 2.58E
7.1 - 5.9 = 2.58E
E = 1.2/2.58
E = 0.465
The statistical test that would be most appropriate determine the answer the researcher is interest in knowing is a chi-square test.
<h3>
What is a chi-square test?</h3>
A chi-square test is a statistical test used to test the relationship between categorical variables. It is used to determine the difference between the expected data and the observed data is due to chance.
Chi squared = 
Where:
= observed value
= expected value.
The researcher is interested in knowing if the response to lowering the legal age for drinking alochol (observed value)) varies by gender (expected value). Thus, a chi-square test would be used.
To learn more about chi-square, please check: brainly.com/question/14082240
Volume of a cone = [(pi)r^2(h)]:3 = [3.14 (25m^2)(12m)]:3 = 314in^3.
Answer:
b. The boundary line of y < 2x - 3 is not a solid line.
Step-by-step explanation:
It's a linear inequality thus its boundary line must be a solid line.
