Answer:
The number of rainfalls is
The answer to the second question is no it will not be valid this because from the question we are told that the experiment require one pH reading per rainfall so getting multiply specimens(used for the pH reading) from one rainfall will make the experiment invalid.
Step-by-step explanation:
from the question we are told that
The standard deviation is
The margin of error is
Given that the confidence level is 95% then we can evaluate the level of significance as
Next we will obtain the critical value of from the normal distribution table , the value is
Generally the sample size is mathematically represented as
substituting values
The answer to the second question is no the validity is null this because from the question we are told that the experiment require one pH reading per rainfall so getting multiply specimens(used for the pH reading) from one rainfall will make the experiment invalid
Answer:
The circle is the shape with the largest area for a given length of perimeter. ...
The circle is a highly symmetric shape: every line through the centre forms a line of reflection symmetry and it has rotational symmetry around the centre for every angle. ...
All circles are similar.
Answer: B, E
Step-by-step explanation:
9514 1404 393
Answer:
- 57 = (7/8)x -13
- $80
Step-by-step explanation:
1. I find it convenient to use variable names that remind me what they stand for. Here, we can use "j" to represent Joanne's earnings, and "e" to represent Erin's earnings.
j = 57 . . . . . Joanne earned $57
j = (7/8)e -13 . . . . . Joanne's earnings were $13 less than 7/8 of Erin's
Substituting for j, we get one equation for Erin's earnings
57 = (7/8)e -13
Using 'x' for Erin's earnings, this is ...
57 = (7/8)x -13
__
2. We can solve the equation as follows:
70 = 7/8x . . . . . . add 13
80 = x . . . . . . . . . multiply by 8/7
Erin earned $80 in tips.