Answer:
a. difference of means
Step-by-step explanation:
Given that :
Mean , x = 9.4
Standard deviation,
= 2.5
Number,
= 12
Mean, y = 6.5
standard deviation,
= 2.4
Number,
= 12
The null hypothesis is : 
The alternate hypothesis is : 
Level of significance,
= 0.1
From the
= 1.363
Since out test is right tailed.
Reject
, if 
We use the test statics,





The value of
with minimum
that is 11 df is 1.363
We go
and
= 1.363
Decision making:
Since the value of
and we reject the 
The p-value : right tail 
= 0.00724
Therefore the value of
, and so we reject the 
Thus we are testing 'the difference of means" in this problem.
1. Check the picture at the bottom.
2. ABCD is a right trapezoid so the diagonals have equal length. Lets find diagonal BD.
3. In triangle ABD we are given the length AB=7, AD=5 and m(A)=80°.
4. We use the cosine law: 
5. Cosine of 80 can be found with a scientific calculator or in the internet as cos80=0,17
6. 
square root of BD=7.88, so the answer is 8 feet.
Answer:
1.B 2.B 3.B 4.B
Step-by-step explanation:
They are all B 0_0
Answer:
Step-by-step explanation:3,339,933
Answer:
Subtract 4 from each side
Step-by-step explanation:
x + 4 > -8
Subtract 4 from each side
x + 4-4 > -8-4
x>-12