Rockettes

Connecticut, Texas, Nebraska and Virginia, two each. Louisiana, Rhode Island, Kentucky, Washington, Kansas, Wisconsin, Alabama, North Carolina, Utah, Illinois and New Hampshire, one each. Two come from Australia, five from Canada.

HOW DO THEY LOOK THE SAME HEIGHT IF THEY’RE NOT?

Heels? Optical illusion? “The way we line up is we put the taller girls in the center and gradually go down to the shorter girls on the end,” says LaVergne. “There’s a bit of an illusion, but it’s actually really simple.” The costumes are made proportionately, helping the illusion.

DURING HIGH KICKS, HOW TIGHTLY DO THEY HOLD EACH OTHER?

Prepare to be astonished: “We actually don’t touch each other,” says LaVergne. The dancers just lightly brush the women beside them with outstretched arms. They call it “feeling the fabric.” That ensures they’re in line without pushing or leaning. “It just looks like you’re actually holding onto your neighbor, but we don’t,” says LaVergne.

BEST PLACE TO BE ON THE LINE?

Doesn’t matter. “Whether you’re on the end or the center, you’re still kicking on your own,” says LaVergne. Each dancer relies on back muscles, core strength and hamstring and quad power, not pushing off another dancer. “Whether you’re standing on zero or 36, you’re going through the exact same experience,” says Callahan.

QUICKEST COSTUME CHANGE?

Between the “Parade of the Wooden Soldiers” and “New York at Christmas,” the Rockettes have just 78 seconds to change outfits. That means taking off socks, shoes, pants, jackets, gloves, cheeks and hats, then putting on dresses, shoes, jackets, earnings, gloves and new hats. Wait, what’s that about “cheeks”? The Rockettes wear red cloth cheeks for “Parade of the Wooden Soldiers” and “Rag Dolls” for rosy complexions.

WHAT DO THEY EAT?

Everything. Catered foods include proteins, veggies, salads, carbs, desserts. Bottles of sports drink Powerade are everywhere. In her dressing room, LaVergne has chips, popcorn, yogurt and apples. Callahan’s go-to snack is a peanut butter and banana sandwich. She also has a stash of M&M’s.

BEFORE THE CURTAIN RISES …

They’re onstage in reindeer costumes, the overture is playing, and they’re hidden by a curtain. Some stretch, some pray, some test their antler lights. Others do a clap routine, high fives or dance with a friend. Callahan does three splits, every time.

“Because it’s so perfect and precise onstage once the curtain opens,” says LaVergne, “to see everyone doing something different is hysterical.”

STAYING HEALTHY

Vitamins, water, rest, good nutrition, CleanWell hand sanitizer. LaVergne likes Emergen-C packets. Callahan is partial to electrolyte tablets. Yearround, Callahan likes yoga, Pilates and barre classes. LaVergne leans toward boot camp, boxing and interval training.

COOL DOWN LIKE A ROCKETTE

Many dancers take an ice bath before heading home. Callahan sits in a tub in 45-degree water to reduce inflammation.

IS THAT TAPPING REAL OR RECORDED?

Oh, it’s real. For the tap-dancing numbers “Rag Dolls” and “The Twelve Days of Christmas,” wireless microphones are hidden in their tap shoes’ arches.

MOST EMBARRASSING MOMENT

For Callahan, it was a 2013 fall onstage, opening night in “The Twelve Days of Christmas” tap number: “It felt like an eternity on the floor but was probably two seconds. You had to keep smiling, keep going, pretend like nothing ever happened.” LaVergne recalled the time a fellow Rockette’s shoe came off during a high kick and went sailing — luckily away from the audience. She kept going. Santa picked up the shoe like nothing happened.

IS THERE ANY HAZING FOR NEWCOMERS?

Are you crazy? This show demands absolute precision and teamwork. There’s no room for veterans to make freshmen feel lousy. They might offer advice, but no bullying.

“We’re all in it together,” says LaVergne. “If you don’t have that camaraderie and we don’t have that bond, it will show onstage.”