Plants have cell walls, but animals do not because otherwise we wouldn't be able to move.
Light is refracted when it crosses the interface from air to glass in which it moves more slowly.
Since the light speed changes at the interface, the wave length of the light must change too. The wave length decreases as the light enter the medium and the light wave changes direction.
1 watt = 1 joule/sec
1800 watts = 1800 joules/sec
(1800 J/sec) x (20 min) x (60 sec/min)
= (1800 x 20 x 60) joules = 2,160,000 joules .
( 2.16 megajoules )
The answer is false. The speed of the astronaut cancels out the force of gravity, causing a 'stationary freefall'. While under these effects, it is not required for an astronaut to 'strengthen' his body.
Answer:
it loaded and it is C. buddy sorry about that :)