Sarah bought 8 folders and 3 rulers. lea bought 8 rulers and 3 folders. sarah paid $1.25 more than lea. how much was each folder if each ruler was .45

Koji is installing a rectangular window in an office building. the window is 823 feet wide and 534 feet high. the formula for the area of a rectangle is a=bh. what is the area of the window? enter your answer as a mixed number in simplest form in the box. $$ ft2

Someone me! will award brainliest if u explain and answer!

The equation for two lines in the coordinate plane are 2dx+y=4 and -6x+y=3, where d represents an unknown value. what value(s) of d would make these lines parallel?