Does parallel lines meet to form an acute angle??

Asequence of numbers begins with 12 and progresses geometrically. each number is the previous number divided by 2. which value can be used as the common ratio in an explicit formula that represents the sequence? 1/2 2 6 12

Given the two similar triangles, how do i find the missing length? if a=4, b=5, and b'=7.5 find a'

Can some one explain this i got sent this. is this a threat i’m scared