68. Find the volume of this square-based pyramid. (meters)

A. 810 m2
B. 270 m2
C. 405 m3
D. 180 m3
E. 60 m

1. 0.3 •4 is the same as 4 groups of 0.32. 7•0.8 is the same as 7 groups of 0.83. it increases by 0.5 every time, so 0.5x4 it increases by 0.9 every time, so 0.9x5. 0.9•12=10.86. 0.47•5=2.35i can finish the next ones in a separate post