When the ventricles contract to pump blood out to the body and lungs, the valves between the upper chambers (atria) and lower chambers (ventricles) snap shut to prevent blood from flowing backward. That sudden closure and the vibration of the valves and surrounding blood create the low-pitched "lub" sound.
The closing of the atrioventricular (AV) valves — specifically the tricuspid valve (right side) and the mitral valve (left side) — at the beginning of ventricular contraction (systole).
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AM I GOING TO HAVE TO PRINT THE PDF FILE IT CREATED?
If you file your tax return electronically, you should not have to print it. You can keep an electronic copy for your tax records.
I am seeing conflicting information about the standard deduction for a single senior tax payer. In one place it says $$16,550. and in another it says $15,000.00. Which is correct?
For a single taxpayer, the standard deduction (for 2024) is $14,600. For a taxpayer who is either legally blind or age 65 or older, the standard deduction is $16,550. For a taxpayer who is both legally blind AND age 65 or older, the standard deduction is $18,500.
For 2025, the standard deduction for single taxpayers (without adjustments for age or blindness) is $15,000.