Answer:
The true weight of the aluminium is
4.5021 kg
Explanation:
Given data
= 4.5 kg
= 1.29 
= 2.7× 
The true mass of the aluminium is given by

Put all the values in above equation we get

4.5021 kg
Therefore the true weight of the aluminium is
4.5021 kg
Velocity, because if an object is in motion with no direction we will consider it as speed, but if it has direction we will consider it as Velocity. Hope it helps
De broglie wavelength,
, where h is the Planck's constant, m is the mass and v is the velocity.

Mass of hydrogen atom, 
v = 440 m/s
Substituting
Wavelength 

So the de broglie wavelength (in picometers) of a hydrogen atom traveling at 440 m/s is 902 pm
Answer:
1/8 = (1/2)^3
This implies the sample has decayed for 3 half lives
3 * 5730 yrs = 17,200 years