Which material is very strong and tough but shows very little elongation as it absorbs energy?

kevlar

Explanation:

Kevlar is a manufactured plastic, and it's made of a chemical compound called poly-para-phenylene terephthalamide. This chemical is made from creating a chemical reaction between an acid and a chemical solution containing nitrogen and hydrogen. Kevlar is a type of aramid fiber. It is woven into textile materials and is extremely strong and lightweight, with resistance toward corrosion and heat. It is used in vast applications such as aerospace engineering (such as the body of the aircraft), body armor, bulletproof vests, car brakes, and boats. Kevlar also has a very long plastic deformation range and when it fails it does so one strand at a time and will even bend or fall over instead of snapping. It has a much more predictable and forgivable failure mode compared to other fibers like carbon fiber.

1. a)c-14 has two more protons

2. d)they have different numbers of protons, neutrons, and valence electrons; they are all gases at room temperature.

3. c) iron and nickel.