Answer:
4 hours
Step-by-step explanation:
Ratio of working together
Job : number of hours
1 : 3 = 1/3
Trainer
Job : number of hours
1 : x = 1/x
Trainee
Job : number of hours
1 : 3x = 1/3x
1/x + 1/3x = 1/3
Multiply through by 3x
3x(1/x) + 3x(1/3x) = 3x(1/3)
3 + 1 = x
4 = x
x = 4 hours
It takes the trainee 4 hours to finish the job
Method 1.
Use the formula of a distance between two points:

We have

substitute

Answer: 10
Method 2
Look at the picture.
Use the Pythagorean theorem:

Answer: 10
Answer: $443.32
Step-by-step explanation:
Hi, to answer this question we have to calculate perimeter of a semicircle:
P = π (d/2) + d
Where d is the diameter
Replacing with the values given:
P = 3.14 (23/2) + 23 = 59.11 feet
Since each linear foot cost $7.50, we have to multiply that cost by the perimeter.
59.11 x 7.50 = $443.32
Feel free to ask for more if needed or if you did not understand something.
Answer:
Describe two ways you think a sound wave could be stopped or could change change direction.