According to the formula

Where a is work, f is force and d is the distance that box was moved over. And from that formula, you can get that f = a/d and that is 54.83N of force
W=mgh
W=(6)(9.8)(4)
W= 235.2J
To answer this question, we should know the formula for the terminal velocity. The formula is written below:
v = √(2mg/ρAC)
where
m is the mass
g is 9.81 m/s²
ρ is density
A is area
C is the drag coefficient
Let's determine the mass, m, to be density*volume.
Volume = s³ = (1 cm*1 m/100 cm)³ = 10⁻⁶ m³
m = (1.6×10³ kg/m³)(10⁻⁶ m³) = 1.6×10⁻³ kg
A = (1 cm * 1 m/100 cm)² = 10⁻⁴ m²
v = √(2*1.6×10⁻³ kg*9.81 m/s²/1.6×10³ kg/m³*10⁻⁴ m²*0.8)
<em>v = 0.495 m/s</em>
The flow of Direct current (DC) is constant and flows in one direction. Most digital electronics make use of DC. Alternating current (AC) periodically flows in reverse and is mostly used to deliver power to houses, buildings and the like. With that alone, you can already rule out A, C and D.
The answer would then be B. constant, periodically reversing.
Almost all of the energy on Earth comes from the Sun
The energy in fossil fuels originally came from the Sun
Plants convert the energy
Explanation:
The sun is the ultimate source of energy on earth and even the whole of the solar system. The sun drives and powers all external processes on earth. It produces its energy from the nuclear fusion of lighter nuclei into heavier ones.
- Almost all of the energy on earth comes from the sun. A few component of the energy on the surface comes from the internal heat engine.
- The energy of fossil fuels originally came from the sun. This is because, plants stores the energy in the process of photosynthesis. When they die and the energy is not released, the energy is stored as fossil fuels.
- Plants in the process of photosynthesis converts the energy. Here green plants combines carbon dioxide and water in the presence of sunlight.
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Convection brainly.com/question/1140127
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