Cho hình chóp SABCD có ABCD là hình vuông tâm O cạnh 2a, SA vuông góc (ABCD), SC=4a. Gọi M là trung điểm SC a/ Tính thể tích S. ABCD, S. OCD, M. ABC
b/ Tính góc giữa SC và mặt đáy
c/ Tính khoảng cách từ A đến (SBC)
d/ Tính khoảng cách từ O đến (SCD)

step-by-step explanation:

this woman was an important writer and propagandist during the american revolution. she was a member of the committee of correspondence (in fact the committee was formed in her home) and was an advisor to many of the revolutionary leaders, including george washington and john adams. who was this revolutionary woman?

mark other person brainliest

18

step-by-step explanation:

draw the shape and you will see that f and k are actually at adjacent vertices (points of the hexagon that are neighboring).   so find the distance between (1,2) and (4,2).   that is easy since (1,2) and (4,2) is just a vertical distance to count, which is 3.   it is a regular polygon which means all sides are congruent.   you have 6 sides (hexa) so multiply 6 by 3 to receive 18.