Answer:
I think it is meteorologist because they also study of the atmosphere, atmospheric phenomena, and atmospheric effects on our weather.
The culture that gave the visiting Europeans eyeglasses and silk fabric was the Chinese civilization. The Chinese invented eyeglasses over a 1,000 years ago<span>, according to British scientist and historian Sir Joseph Needman. By the time Marco Polo arrived in China around 1270, eyeglasses (which he mentions in his accounts) were widely used in Chinese upper class. On the other hand, s</span>ilk has been used by the Chinese for approximately 5,000 years.<span> The earliest evidence of silk dates back to around 4,000-3,000 BC in Shanxi province, where a culture silk cocoon was found.</span>
Once all hydrogen is depleted the star begins to die
Answer:
U₁ = 129.4 J
Explanation:
The potential energy is
U = mg y - m g y₀
Where I correspond to the initial position, with this it is an additive constant, we can make it zero with the placement of the reference system, in this case the system is placed on the floor where the ladder rests.
The power power for people on the floor is
U₀ = 0 J
The potential energy for the person on the first step is
U₁ = m g y₁
In general the steps are 20 cm high
y₁ = 20 cm (1m / 100cm) = 0.20 m
U₁ = 66 9.8 0.20
U₁ = 129.4 J
