Tools used by geologists

Which of the following is an example of an iron triangle?

Why did alexander give the soldier who saved the hat band a reward? why did he then order the man's head cut off?

After the success of the sputnik launch, the united states feared that they would never be able to launch their own satellite, the ussr had used technology developed by the united states, the soviets had superior nuclear capabilities, that any future us satellites would not be as successful.