Isobars and isotherms are both lines on weather maps that represent patterns of pressure and temperature. They show how temperature and pressure are changing over space. They describe the large-scale weather patterns across a region in the map.
This paragraph should help you out :)
I would say by using a telescope to look into the sky
Secondary vents<span> are smaller outlets through which magma escapes.</span>
Using Pythagorean's Theorem of a^2+b^2=c^2, with a and b being two legs and c being the hypotenuse.
You can find that the leg(15) squared is 225. The hypotenuse(17) squared is 289.
289-225=64
The square root of 64 is 8
So the missing leg of the triangle has a length of 8 units.
