Answer:
C. 666
Step-by-step explanation:
USING PEMDAS we can solve this problem.

SA=2H(L+W)+LW for open box
20=2H(4+W)+4(W)
distribute
20=8H+2WH+4W
divide both sides by 2
10=4H+WH+2W
solve for 1 variable, pick W
10-4H=WH+2W
10-4H=W(H+2)
(10-4H)/(H+2)=W
V=LWH
subsitute 4 for V, subsitute H for H and (10-4H)/(H+2) for W
V=(4)(H)(10-4H)/(H+2)
V=(40H-16H²)/(H+2)
find max value
take deritivitive of this thing
V'=-16(H²+4H-5)/((H+2)²)
using sign chart
sign changes from positive to negative at H=1
so at H=1
find W
W=(10-4H)/(H+2)
W=2
the dimeionts are
length=4ft
width=2ft
height=1ft
(the volume is 8 cubic feet)
Answer: c. z = 1.35; Reject the null hypothesis
Step-by-step explanation:
Let
be the average life expectancy of its batteries.
As per given , we have
Null hypothesis : 
Alternative hypothesis : 
Since
is right-tailed and population standard deviation is also known, so we perform right-tailed z-test.
Test statistic : 
where, n= sample size
= sample mean
= Population mean
=population standard deviation
For
, we have

Critical one-tailed test value for 0.10 significance level :

Decision : Since critical z value (1.28) < test statistic (1.35), so we reject the null hypothesis .
[When critical value is less than the test statistic value , we reject the null hypothesis .]
Answer:
32r + 39
Step-by-step explanation:
<u>Step 1: Distribute</u>
4(5 + 8r) + 19
<em>20 + 32r + 19</em>
<em />
<u>Step 2: Combine like terms</u>
<em>32r + 39</em>
<em />
Answer: 32r + 39
Answer:
Your welcome
Step-by-step explanation:
$8160 the hours would be 480
$680 the hours would be 40
$35,360 the hours would be 2,080
$36,720 the hours would be 2,160