How did farmers primarily protect themselves from invaders during the Han dynasty?

They built brick homes to keep safe from nomads.
They paid taxes in crops in exchange for protection.
They grew silkworms and traded them for weapons.
They lived in small villages to avoid attracting enemies.

What are the three criteria necessary to qualify for special education services under the individuals with disabilities education act category of intellectual disabilities? an intellectual functioning of 70 or more on a standardized iq test significant difficulty with tasks of everyday living (adaptive behavior) subaverage intellectual function (2 or more sd below the mean on a standardized iq test) impaired intellectual performance due to a traumatic brain injury deficits in intellectual functioning occur during the developmental period to distinguish id from other disabilities

One way in which the european union encourages trade among countries is through the use of

How do the public-safety regulations protect workers ? regulations create advertising laws