In-facepiece dust concentration is changed dozens of times in a matter of minutes due to changes of the size of the gaps between the mask and face. Source. A respirator is a device designed to protect the wearer from inhaling particulate matter, including airborne microrganisms, fumes, vapors, i.e. gases.
Why join Brainly? A community for students. Products of the neolithic culture Steel plows Boats with sails Domesticated dogs Wild figs. the answer would mostly likely be referring to things that actually were of use to the neolithic people and agriculture was the biggest thing making the answer steel plow. anonymous.
In 1865, Lubbock distinguished the Neolithic as when polished or ground stone tools were first used: but since Lubbock's day, the definition of Neolithic is a package of characteristics: groundstone tools, rectangular buildings, pottery, people living in settled villages and, most importantly, the production of food by developing a working ...