Answer:
5730 years
Explanation:
The half life of carbon-14 is 5730 years. If 50% of the carbon-14 remains, then exactly 1 half life has passed.
The half-life equation is:
A = A₀ (½)^(t / T)
where A is the remaining amount,
A₀ is the initial amount,
t is time,
and T is the half life.
In this case, A = ½ A₀ and T = 5730.
½ A₀ = A₀ (½)^(t / 5730)
½ = (½)^(t / 5730)
1 = t / 5730
t = 5730
The mass of the bird is 0.32 kg.
<u>Explanation:</u>
Gravitational potential energy, the energy exhibited by an object at rest due to the influence of gravitational force. So the increase in distance of object from the surface of earth leads to increase in the gravitational potential energy. Thus,

So, as the gravitational potential energy is given as 2033 J and the position of bird placed on the tall tower is 639 m away from the bottom, then the mass (m) of the bird can be found as below.

So, finally we get the bird's mass as,
m of bird = 0.32 kg
Answer:
In the more scientific viewpoint, the most important thing that she must do is caring for her hygiene and put some plastic gloves in her hands.
This is because there are lots of particles that can be retained in the hands (dust, skin, etc), and when examining the scene, she may drop some of these particles, "contaminating" the scene in this way with information that only will affect the investigation.
So the most important thing is being prepared to not affect anything in the crime scene