help plz asap plzzzzzzzzzzzzzz

Answer:
2.8
Explanation:
Firstly....find the ratio between the two shapes
i.e we take JK and AB...which are the similar sides
; AB/JK = 3/2.1 = 1.428...this value should be the same for all pairs of sides that are similar
; Then for side KL...,
;we use the formula
BC/KL = 1.428
4/KL = 1.428
;Where KL = 4 ÷ 1.428
;Hence side KL = 2.8