Question

"a dam is thicker at the bottom than at the top partly because"

Answer 1

Dam is thicker at the bottom because there is more pressure of water in bottom because of its long height and low pressure at top

Answer 2

As increase the level of water stored in a dam ,the pressure exerted by the water to the walls of dam increases gradually. So to handle this great pressure ,the walls of fans are thicker at the bottom than at the top.
if you found it useful please mark my answer as brainliest.