1. C-4 explosives
   Heavy machine gun
2. Atomic bomb

In 1942, the Manhattan Project set out to do what no other science project had ever done -- build a nuclear bomb. After years of work, the Allies used the fruits of their labor to demolish Hiroshima and Nagasaki.

1. Bulletproof vests/armor
   Radar
2. Aeroballistics

Radar was in its infancy at the start of the war, but by the end, both sides were using the technology to track vehicles at long ranges. In many cases, advanced radar made surprise attacks virtually impossible.

1. They are "nearly" weapons.
   They trigger explosives when a target is close.
2. They spread out bombs over a large area.

WWII saw the introduction of proximity fuzes, which can detect how far away a target is -- and then detonate explosives at just the right time. These fuzes basically use tiny radar devices to work their magic.

1. Remote-control gun turret
   Prayer
2. Lasers, lots of lasers

The B-29 bomber had four amazing remote-control machine gun turrets, as well as one semi-remote tail gun. The guns used a state-of-the-art computer-controlled fire-control system unlike anything the world had ever seen.

1. True
2. False

Although jet fighters were still a very new concept by the end of the war, both sides did deploy them. And these planes were so fast and so deadly that they made planes from the war's start look harmless by comparison.

1. True
2. False

The bombs, named Fat Man and Little Boy, were different technologies. Little Boy was a uranium gun-type bomb. Fat Man, on the other hand, was a plutonium implosion-type bomb. Both were devastatingly effective.

1. aircraft carrier
   transport aircraft
2. tank

The Germans went big on a lot of their projects, including the Messerschmitt Me 323, the largest transport plane in the war. The enormous plane could transport about 12 tons of gear or up to 130 troops.

1. It was an accident.
   In case one of them didn't work.
2. They intended to use both types.

Because nuclear weapons are so complex, the scientists weren't sure if the first weapon would work. So they built two types of bombs in hopes that at least one of them would function. Turns out, both designs were successful.

1. Radar
   Infrared technology
2. Nuclear bombs

When the Axis began using radar to track Allied planes, the bombers began dropping strips of tinfoil ("chaff") meant to confuse radar. The chaff was simple but often very effective.

1. He was Ike's personal doctor.
   He created the Turing machine.
2. He designed a special type of boat.

Higgins designed the Higgins Boat, the LCVPs (Landing Craft, Vehicle and Personnel) that were used for D-Day, the biggest amphibious assault in history. The cleverly designed boats were the only way the Allies could land on open beach near shallow waters.

1. It was a rocket-powered fighter.
   It shot spider webs as weapons.
2. It was equipped with extra swastikas.

The Komet was the first attack fighter with rocket power. It was so fast that the Allies gave up trying to attack it in the air, instead shooting it during the slower speeds of takeoff and landing.

1. About 130
   About 1,300
2. About 130,000

More than 130,000 people participated in the science and labor of making the first atomic bombs. In the end, their efforts transformed modern warfare and politics.

1. ground-to-ground artillery
   air-to-air missile
2. air-to-ground bomb

Germany managed to develop the Ruhrstahl X-4, the world's first air-to-air missile during the war. However, this wire guided invention never made it into combat.

1. A supersonic helicopter
   An explosive barge
2. A piloted bomb

The Japanese developed the Yokosuka MXY-7 Ohka, which was basically a rocket-powered bomb. The catch? It had to be guided by a pilot who was guaranteed to die in the attack.

1. Wood
   Plastic
2. Desperation

The Germans developed the Junkers Ju 322 to transport cargo into combat areas. The glider, which was never built, was specifically made to be built from materials that weren't precious to the war effort … so it was designed to be made out of wood.

1. They wanted to steal the plans instead of making their own.
   They were too dumb.
2. Lack of resources

Unlike the Allies, the Nazis didn't have the huge manpower and resources necessary for nuclear bomb research. Compared to the Americans, they barely got their nuke project off of the ground.

1. Digital map screen
   Fully automatic piloting
2. Pressurized cabin

At extreme altitudes, most bombing crews relied on oxygen masks, which often failed and made it hard to move about the plane. The B-29 was the first plane to feature a pressurized cabin, making the crew's jobs much easier.

1. IPAD
   ICBM
2. GPS

Germany took huge strides in creating the V-2, the world's first intercontinental ballistic missile (ICBM). It had a range of just over 200 miles, but the weapon was incredibly advanced.

1. It was half the size of a pack of cigarettes.
   It included dehydrated beer.
2. It provided superior sustenance.

During WWII, American scientists -- for the first time -- put major thought and effort into foods and how they interacted with the human body. They invented the D-ration meal, roughly the same size as a pack of cigarettes, meant to sustain troops on the battlefield in the worst of conditions.

1. Many remained in service.
   Most were immediately salvaged.
2. They were sold to China.

Most WWII-era bombers were obsolete after the war. No so with the ultra-advanced B-29. Many of these planes remained in active service long after the war ended.

1. "Boat to the bottom of the sea"
   "Bridge to the beach"
2. "Big, ugly boats"

Higgins boats were specially designed to cross shallow water and take men ashore. They were the critical "bridge to the beach," one that many terrified troops probably wish they had never boarded.

1. True
2. False

German V-2 missiles had incredible guidance systems that could send the munitions into a target hundreds of miles away … without any sort of input from operators on the ground.

1. A napalm bomb
   A mechanical flashlight
2. A Zippo lighter

Because power shortages were routine during the war, engineers at Philips created the "dyno torch," a mechanically-powered flashlight. To make it work, troops pressed the button over and over again.

1. The overworked scientists had a fun bonfire to celebrate the end of the war.
   Because no one would ever need a nuclear weapon again.
2. To prevent the Communists from getting them

Many of the plans for the world's first nuke were discarded following the war. Why? Because everyone figured the time for a nuclear weapon had come and gone.

1. To detect Allied troop movements
   To encrypt messages
2. To calculate when doomsday would arrive

The Nazis used the Engima machine to encrypt their messages … and for a long time, the code seemed to be unbreakable. But circumstances favored the Allies, who finally cracked the machine and then intercepted many Axis messages.

1. M1 Garand
   Manhattan Project (atomic bomb)
2. B-29 Superfortress

While completing the Manhattan Project cost roughly $22 billion in today's dollars, it was production and material costs of the super-advanced B-29 program that amounted to a couple of a billion more.

1. Tank tread
   Radar
2. Cloaking

The P. 1500 Monster was designed to travel on four enormous tank treads, each driven by a diesel engine generating about 2,200 horsepower.

1. A wooden glider
   A self-propelled gun
2. Amphibious assault vehicle

The Germans built the Landkreuzer P. 1500 Monster, a gigantic self-propelled gun that was just as scary as the name implies. The ridiculously large gun was 138 feet long and weighed nearly 1,500 tons.

1. B-29 Superfort cannon
   Sturmgewehr 44 assault rifle
2. Landkreuzer P. 1500 Monster

The gigantic infrared devices were unwieldy, but obviously allowed snipers to find their targets much more easily at night.

1. A huge machine gun cartridge
   A type of bomb
2. The world's first programmable digital computer

In the 1940s, British codebreakers built Colossus, the world's first digital computer, in an effort to crack Axis codes. It was a top-secret program that paid many dividends during the war.