As per Kepler's third law we know that

now here we know that
= year of Neptune
= year of Earth
= distance of Neptune from Sun
= Distance of Earth from Sun
so now we will have



so length of year of Neptune is 164.3 years
Answer:

Explanation:
Let the child is moving with speed same as the speed of water flow
So here the position of child with respect to flow must be zero
And if the boat start at an angle with the vertical
so its relative speed with flow of water is given as


now the time to reach the child is given as

so now we have

So the time to catch the child is given as


So distance moved by it in 0.104 h
distance moved by the boat in upstream direction given as


In y direction the displacement of boat is

net displacement of the ball is given as



Oh ya the correct answer for this is B I think because structure B
Answer:
The sound travels differently in different medium according the density of the medium.
Explanation:
The sound travels faster in dense medium and can be heard by the vibration of the bone present in the ear. The ear plugs reduce the sound intensity in both medium water and on land (air).
In air the sound is not heard properly due to the earplugs that stops the as the vibration are not able to produce as sound is not able to reach to middle ear, but Navy researchers have discovered that sound under water is heard by the bone present behind the ear, vibrations mastoid.
Base SI unit is the unit that used for simple quantity like time=second and length= meter. They only have one unit.
Derived unit is more complex because you multiply or divide at least two base SI, making it have more than 1 unit. The example could be velocity which was time/length = m/s