Answer:
1
Explanation:
How many digits are in front of the decimal in scientific notation?
Distance = (30+40+50) = 120 km
It's back where it started, so displacement = zero
Answer:

Explanation:
Rydberg formula is used to calculate the wavelengths of the spectral lines of many chemical elements. For the hydrogen, is defined as:

Where
is the Rydberg constant for hydrogen and
,
are the lower energy state and the higher energy state, respectively.

Kinetic energy = 1/2 * m * V^2
K = 1/2 * 2kg * 4
Work = force × distance, assuming that the force is parallel to displacement.
Work L=75×5=375J