Answer:
at ( or below)
Explanation:
at the dewpoint.......water will condense out of the air onto the surface
<span>Our eyes can detect visible radiation, our skin can detect infra-red, our skin can also react to ultra-violet radiation by tanning, and producing skin cancers.
</span>Our brains can react directly to the impact of gamma rays ( as "seen" by astronauts )
<span>and some microwaves will cause us to heat up internally.
</span>
<span>While radio waves and ELF waves seem to ignore us totally without the aid of aerials and amplifiers. </span>
If Earth’s distance from the sun increased by 4 times then the speed of Earth’s orbit around the sun would decrease by a factor of 2.
Answer: Option 3
<u>Explanation:</u>
From Newton’s second law of motion, it is known that any kind of external force acting on an object will be equal to object’s mass and acceleration exerted on the object. So in this case, the gravitational force between Earth and Sun will be equal to the mass (M) and acceleration exerted on Earth.

It is known that,

Thus, substituting this, we get,

Also, we know,

Then, comparing both the equation, we get the orbital velocity as,

So, here G is gravitational constant, M is the mass of Sun and r is the distance of separation of Earth from Sun.
If the distance of Earth from Sun increases by 4 times so r’ will be 4r. Thus the new orbital velocity v’ will be

So,

Thus, the orbital speed will be decreased by a factor of 2 when the distance of Earth from the Sun increased by 4 times.