Answer:
a) α=7.9x10^-4 rad
b) θ=1.12x10^-4 rad
c) The Earth and the Moon cannot be seen without a telescope.
Explanation:
In this exercise we will use the concepts of angular resolution, which depends on both the wavelength of the rays and the diameter of the eye or lens on the meter. Its unit of measure is the radian. The attached image shows the solution step by step.
Answer:
The mass of Uranium present in a 1.2mg sample is 
Explanation:
The ration between Uranium mass and total sample mass is:
For a sample of mass 1.2 mg, the amount of uranium is:

It will sink because mass does not affect the physical properties of the object.
The answer is Air Resistance