DEAR READERS: Suspect a STROKE? Act F.A.S.T. The National Stroke Association (www.stroke.org) suggests looking for these danger signs:

F. (FACE): A droopy face when smiling.

A. (ARMS): Inability to raise both arms at the same time, and with equal height.

S. (SPEECH): Slurred or garbled speech when reciting a simple phrase or song.

T. (TIME): Call 911 immediately if you observe ANY of these symptoms; note the time the symptoms first appeared.

What is a stroke? A stroke can occur when blood flow is cut off to the brain, or when a damaged blood vessel in the brain bursts. Ask your health care provider for more information on strokes.

— Heloise

Why do coins have ridges?

DEAR HELOISE: My friends and I were wondering: Why do most coins have ridges on the sides?

— Regan W., age 10, in Virginia

Regan, Virginia is one of my old stomping grounds!

Coins have ridges (also called “reeded edges”) for a couple of reasons. When coins were first made (many, many years ago), they were composed of real silver and copper. Unscrupulous people could shave down an unridged coin, collect the shavings and sell them. Nickels and pennies are made of less desirable metals, so no ridges. The ridges also make the coins harder to copy (counterfeit). Thanks for your letter!

— Heloise

Clean car

DEAR HELOISE: I’ve heard that a clean car is more aerodynamic than a dirty car. Is this true?

— Becky D. in Ohio

Becky, yes, it’s true. Dirt on the car creates drag, which “grabs onto” the car and slows it. In one experiment, a dirty car got 24 miles to the gallon, and when the same car was cleaned, it got 26 mpg. The air flows more easily over a clean car.

And don’t worry: Many car washes today have a high-pressure wash, which uses less water and is more friendly to the environment.

— Heloise

No-No for night-night

DEAR HELOISE: I ALWAYS remove my eye makeup before I go to bed. It can flake off and actually damage the cornea. I keep makeup wipes on my nightstand.

— Sarah P. in Texas

Letter of laughter

DEAR HELOISE: A friend of mine used to call getting together with her older friends “getting together for an organ recital.”

Real or imagined organ issues were always the main topic of conversation!

— Sandra F., San Pedro, Calif.

Send hints to Heloise at P.O. Box 795001, San Antonio, TX 78279-5001, or Heloise@Heloise.com.