Answer is: 4-ethyl-1-heptene.
Structure of this alkene is in Word document attached.
First find main chain with longest number of carbon atoms, that is chain with seven carbon atoms and it start on the right and going up the three-carbon attachment.
Main chain has double bond between first and second carbon (the lowest number), so it is 1-heptene (alkene).
Substituent is on fourth carbon atom, it is alkyl group with two carbon atoms (ethyl).
