Answer:
Round to a number that is not a decimal.
Answer: 66 because you are adding 2 then 4 then 6 then 8 then 10 then 12 therefore 17+10= 27, and 27+12= 39 and 39+27 equals 66

now, the first one, on the far-left.... can't see the height.. but I gather you do, now as far as its Base area, well, the bottom is just a 12x12 square, so the area of its base is just 12*12
now, the middle pyramid, has a height of 6, the base is also a square, 8x8, so the Base area is just 8*8
now the last one on the far-right
has a height of 8, the Base is a Hexagon, with sides of 6
I got 5200 I'm not really sure but u can check