The pressure at 99 feet below the surface of the ocean is: greater than the pressure at sea level greater than the pressure 33 feet below the surface about 59 pounds per square inch all of the above

 all of the above

Explanation:

The pressure increases as we go down into the ocean.

Thus pressure at 99 feet below the surface of ocean is greater than the pressure at sea level.

Also the pressure at 33 feet below the surface of ocean is greater than the pressure at 99 feet below the surface of ocean.

The weight of the atmosphere exerts a pressure of 14.7 pounds per square inch of force at sea level which is also equal to 1 atmosphere.At depth of 99 feet , the pressure exerted is 4 atm which is almost equal to 59 pounds per square inch.

a mercury barometer is a device that uses the physical properties of mercury in a tube to measure barometric pressure. mercury barometers are used for : -

1. measurement of atmospheric pressure  

2. determining the altitude of a place

3. weather forecasting

4. calibration and checking of aneroid barometers

5. application in fluid mechanics

6. measurement of pressure in aircrafts

7. surface weather analysis

8. preparation of barographs

9. usage in physical sciences like physics, astronomy & chemistry

10. preparation of aircraft altimeters

characteristics of mercury barometer : -

1.used to define and measure atmospheric pressure.

2.on the average at sea level the column of mercury rises to a height of about 760 mm.

3.this quantity is equal to 1 atmosphere.

4.it is also known as standard atmospheric pressure.

5.a barometer in which the weight of a column of mercury in a glass tube with a sealed top is balanced against that of the atmosphere pressing on an exposed cistern of mercury at the base of the mercury column, the height of the column varying with atmospheric pressure.