The area of the top surface of the washer is: 160.14 square mm.
<h2>Step-by-step explanation:</h2>The top of the surface is in the shape of a annulus with a outer radius of 10 mm and a inner radius of 7 mm ( since the diameter of the hole is: 14 mm and we know that the radius is half of the diameter)
Now, we know that the area of the annulus region is given by:
where R is the outer radius and r is the inner radius.
Here we have:
Hence, we have:
The scuba diver's position relative to sea level after the 4.6 minutes is 5.1 ft.
Given:
A scuba diver descends in the water at a rate of 23 1/2 feet per minute for 2.6 minutes.
A scuba diver ascends at a rate of 28 feet per minute for 2 minutes after seeing a big fish.
To find :
The scuba diver's position relative to sea level after the 4.6 minutes.
Solution:
Rate of a scuba diver descending in the water for 2.6 minutes =
Distance covered by a scuba diver in 2.6 minutes =
Rate of a scuba diver ascending for 2 minutes =
Distance covered by a scuba diver in 2 minutes =
The position of scuba diver after 4.6 minutes relative to sea level:
The scuba diver's position relative to sea level after the 4.6 minutes is 5.1ft.
Learn more about ascending rate and descending rate here: