Aluminum is the most common metal in Earth's crust. But before the discovery in 1886 of the process that allowed it to be cheaply extracted from bauxite, aluminum was expensive to process. In 1852, a pound of aluminum cost $545. At those prices, $100 would buy only 83.2 g of aluminum in 1852. Determine the amount in moles that this masses of aluminum represent. ​

first let us lay out the formula for potential

and kinetic energy:

pe = mgh

ke = (mv^2)/2

where: m=mass, v=velocity, g=gravitational

acceleration, h=height

calculating for mass using the known values of

pe:

340j = m (9.81 m/s^2) (50ft) (1m/3.28ft)

m = 2.27 kg

the law of conservation of energy states that

energy is neither created nor destroyed. therefore, the change in kinetic

energy from 50 ft to 35 ft would be equal to the change in potential energy

from 50 ft to 35 ft. however it would be opposite in signs since one is losing

while other is gaining.

ke(35ft) – ke(50ft) = - [ pe(35ft) – pe(50ft]

ke(50ft) = 0 since the brick is initially at rest

ke(35ft) = 340j - 2.27kg (9.81 m/s^2) (35ft)

(1m/3.28 ft)

ke(35ft)

= 102.38 j

some sources quote the lethal dose, for an average 170lbs opiate-naive individual is between 75 and 375 mg