Please help me answer all of these

Determine which expressions represent real numbers and which expressions represent complex number. asaaap! plis!

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

Venita is sewing new curtains. the table below shows the relationship between the number of stitches in a row and the length ofthe row.sewingnumber of stitches length (cm)51 131532024306what is the relationship between the number of stitches and the length? othe number of stitches istimes the length.o. the number of stitches is 3 times the length.