Answer:
143 batteries does Benny need to sample
Explanation:
Given data
confidence level = 97%
error = ±10 hours
standard deviation SD = 55 hours
to find out
how many batteries does Benny need to sample
solution
confidence level is 97%
so a will be 1 - 0.97 = 0.03
the value of Z will be for a 0.03 is 2.17 from standard table
so now we calculate no of sample i.e
no of sample = (Z× SD/ error)²
no of sample = (2.16 × 55 / 10)²
no of sample = 142.44
so 143 batteries does Benny need to sample
Answer: 
Explanation:
Given
Length of the race track 
the radius of curvature of the track 
time taken to run on track is 
Speed of runner is
Centripetal acceleration is
It seems to go against what we see with our eyes. Plus, it contradicted official church doctrine at the time.
As Ampere suggested, a magnetic field is produced whenever an electrical charge is in motion. The spinning and orbiting of the nucleus of an atom produces a magnetic field as does electrical current flowing through a wire. The direction of the spin and orbit determine the direction of the magnetic field.
Darker and lighter dis would be the answer
