What's the question you're asking?
Answer:
$171.12
Step-by-step explanation:
Including the tip and cost, it is 171.12. Multiply 148.6 by 1.15, which includes the total cost plus another 15% for the tip.
Answer:
y = -(x + 5)² + 4
Step-by-step explanation:
The roots are -3 and -7, so:
y = a (x + 3) (x + 7)
Distribute and complete the square:
y = a (x² + 10x + 21)
y = a (x² + 10x + 25 − 4)
y = a (x² + 10x + 25) − 4a
y = a (x + 5)² − 4a
The vertex is (-5, 4), so a = -1.
y = -(x + 5)² + 4
Answer: 16590
Step-by-step explanation:
The formula we use to find the sample size is given by :-
, where p = prior estimate of population proportion.
= Critical z-value (Two- tailed)
E= Margin of error .
Let p be the population proportion of cyanobacteria.
Given : E = 0.01
Critical value for 99% confidence interval : 
If Ian does not want to rely on previous knowledge , then we assume p=0.5 because the largest standard error is at p=0.5.
Now, the required sample size = 

Required sample size = 16590