Hey there,
Question: "<span>What is the half life of Strontium-90? Explain your answer"
Answer: </span>28.8 years / <span>Strontium-90 has 52 neutrons and 38 protons. </span>
Answer:
t = 6.68 seconds
Explanation:
The acceleration of the automobile, 
Initial speed of the automobile, u = 91 km/hr = 25.27 m/s
Final speed of the automobile, v = 104 km/hr = 28.88 m/s
Let t is the time taken to accelerate from u to v. It can be calculated as the following formula as :


t = 6.68 seconds
So, the time taken by the automobile to accelerate from u to v is 6.68 seconds. Hence, this is the required solution.
I don’t know what you are trying to ask complete my but here are the steps to a scientific investigation i hope this helps you
The answer might be C ? hope it's right
The electric field produced by a large flat plate with uniform charge density on its surface can be found by using Gauss law, and it is equal to

where

is the charge density

is the vacuum permittivity
We see that the intensity of the electric field does not depend on the distance from the plate. Therefore, the strenght of the electric field at 4 cm from the plate is equal to the strength of the electric field at 2 cm from the plate: