Why do clouds tend to form above either a flat or a moun- tainous island in the middle of the ocean? (Hint: Compare the specific heat capacity of the land with that of the water and the subsequent convection currents in the air.)

As explained below.

Explanation:

As the winds coming towards the mountain island will flow to the mountain they will get forced upwards and this will raise the temperature of the air above.If there is enough water vapor in the air that can lead to cooling the water vapor will condense and form into a cloud of microscopic droplets.  And thereby it will rain over the mountain peaks and thus the flow of the convective currents in the air will flow upwards and the clouds will surround over the flat mountain. This may create a rain shadow effect.

I'm pretty sure there's a geometry rule for   anyways, if the triangle is equilateral, and the circle is circumscribed, the circle is outside of the triangle.  to find the area, you need the radius.  the radius should be a straight line from the center of the triangle to any of it's points.  draw lines from the center of the circle to each of the triangle points.  draw three more lines from the center to the middle of the sides of the triangle.  you should now have six separate 30-60-90 triangles inside of your original triangle. use your 30-60-90 rules to solve for the radius, then the circumference. 

Ibelieve it's the pacific islands