$32,000 for Married Filing Jointly. $0 for Married Filing Separately if the spouses lived together during the year. If your total income is more than the base amount, you might owe some tax on your Social Security benefits.
Pure water at 60F has about 27.78 inches of water column (INWC or INWG) per psi or approximately 0.43197 psi/ft. This is from memory; but it should be close. Fresh water: 0.43 psi per foot Sea water: 0.44 psi per foot. So, for each additional 10 feet of depth, figure about 4.3 to 4.4 psi increase in pressure. You can calculate this yourself by using the fact that fresh water weighs about 62.4 pounds per cubic foot (pcf) and sea water weighs about 64 pcf.
The pound per square inch or, more accurately, pound-force per square inch (symbol: lbf/in 2; abbreviation: psi) is a unit of pressure or of stress based on avoirdupois units. It is the pressure resulting from a force of one pound-force applied to an area of one square inch. In SI units, 1 psi is approximately equal to 6895 N/m 2. Pounds per square inch absolute (psia) is used to make it clear that the pressure is relative to a vacuum rather than the ambient atmospheric pressure. Since atmospheric pressure at sea level is around 14.7 psi, this will be added to any pressure reading made in air at sea level.