The Secret History of Popcorn

Which piece of evidence BEST explains the cause of the jump popcorn makes?

• This amazing feat is largely due to each kernel’s sturdy, protective outer layer, or hull.

• Steam pressure builds up inside until there is enough to burst the kernel’s tough hull.

• This starch squirting out — called a “leg”— pushes against the bottom of the pot.

• It disproved the popular “rocket” theory that escaping steam launches popcorn into its jump.

But what about the popping sound? People used to think that the cracking hull causes the distinctive “pop” we know and love. But Virot and Ponomarenko found something different.As the starch blossoms into the popcorn flake (as the popped kernel is called), speeding steam echoes around the hollows in the flake to make the popping noise. And the entire process, from exploding kernel to tender white flake, takes just one-fifteenth of a second

• The popping sound that popcorn makes happens because the starch pushes through the hard shell of the kernel

• The popping sound that popcorn makes is caused by the cracking that happens when the hull breaks open.

• The popping sound that popcorn makes happens because it takes one-fifteenth of a second to make popcorn.

• The popping sound that popcorn makes is caused by the echoes of the speeding steam inside of the kernel.

Which sentence from the article is BEST supported by Image 2 in the section "Acrobatic Snack"?

• Explaining the motion, heat energy and sound of popcorn touches on many different fields of science.

• Once it makes its first leap, the popcorn continues to bloom while it spins through the air like an acrobat.

• This makes the kernel jump, much the same way that straightening a bent leg can push you off the ground and into the air.

• Once the hull cracks, the steam causes the starch inside, which is kind of like bread dough, to puff up and force its way out of the shell.

How do Image 2 and text in the section “Acrobatic Snack” develop a coherent understanding of popcorn?

• Both explain the answers to the three questions that Virot and Ponomarenko had about popcorn.

• Both show that the ideal temperature for making popcorn is actually 356 degrees Fahrenheit.

• Both explain that the reason popcorn makes the popping sound has to do with the cracking hull.

• Both demonstrate the steps it takes for a kernel of corn to become a popped piece of popcorn.

Which word goes with "many types"?

• feat

• variety

Which sentence is an example of the word "variety"?

• Kyle works at a shoe store in the mall every weekend.

• Kyle has blue, green, red, black and white running shoes.

Which sentence is an example of the word "feat"?

• Alicia was the first 12-year-old girl to climb to the top of the mountain.

• Alicia is a 12-year-old girl who lives in Nashville, Tennessee.

Which word goes with "accomplishment"?

• variety

• feat

Which sentence is an example of the word "protective"?

• Simon's new boots with the special cleats kept him from slipping on the icy sidewalks.

• Simon walked slowly on the sidewalk because there was a little ice on it.

Which word goes with "shields"?

• protective

• theory