Answer: two signals split into four and three respectively
Explanation:
The spectrum of CH3CH2OCH2CH3 is shown in the image attach. The large multiplicity arises from spin orbit coupling which arises because of interaction of proton magnetic field with bonding electrons. In the spectrum the two CH3 groups are split by CH2_and vice versa. The ethyl groups are chemically and magnetically equivalent but are still split by adjacent protons.
