<span> an atom can chemically combine with another atom is referred to as a chemical bond.</span>
Social forces shape technology both in the form of deliberate social activism and also in unconscious ways. For example, in social activism, large demonstrations against oil pipelines can lead to more rapid development of alternatives to fossil fuels. Somewhat unconsciously, the clogging of cars in tight downtown areas in cities and decreasing parking space gave an impetus to develop new forms of rapid transit like subways and electric articulated buses.
I'm not sure what type of fuel you're talking about. If you mean fossil fuel then kerosene has the highest density of all of the things you listed.
The half-life of Plutonium−239, t1/2 is 2.41 × 10⁴<span> yrs
time taken to reach tolerable level = seven half-lives
= 7 x t1/2
= 7 x </span>2.41 × 10⁴ yrs
= 168700 yrs
= 1.687 x 10⁵ yrs
Hence, the period of time that <span>Plutonium-239 must be stored is </span>1.687 x 10⁵ years.
