Answer:
Mid ocean ridge is formed when old oceanic crust is forced under continental plates.
Explanation:
Ocean basin is a kind of land surface that is present under an ocean and below the water.
Ocean basin contain continental shelf,mid ocean ridge that is found on the sea floor.
The size of ocean basin is equal to the size of an ocean and is found below the ocean.
When, water covers the earth's crust region in the distant past,ocean basin formation occurs.This prcess require long time as spreading of sea floor and tectonic plates takes place.
Ex-Atlantic Ocean basin is formed over million years that is present in the European Continent.
Answer: LET'S TAKE GRAVITY ON EARTH AS 10 N/KG AND ON MOON AS 0.6 N/KG
a) weight=15kgx10N/kg
= 150N
b) weight=15x0.6=9N
c) mass=is the same so 15kg
d) mass is measured in kg, weight in NEWTONS OR 
e) when the gravitational force is zero
Explanation:
As you said p=w/t.
but, w=f×s
=500×5=2500j
t=10s
p=w/t
=2500/10=250 watts
If you sight Polaris at 20 degrees above your Northern Horizon then you know that your latitude is 20 degrees north of the equator.