You know the LAKE. Steep descent in, steep ascent out, unforgiving, subject of the first Mountain Lake Landing Challenge. Now for PART II Explore the lake itself!  The Challenge:  Go to the lake and dive down as far as you can.  That's all.    You may: a. build a sub and fly it to the lake b. build a submersible plane c. transport a submersible rover and drive it to the bottom d. something else very cool I did not think of that is in keep