Businessman Leonard Leontiev was shot dead

Entrepreneur Leonard Leontiev was shot dead while leaving a car at the entrance of his own house. His hereditary property consisted of a brick two-story house, land, ten
petrol stations, a Mercedes car and a cash deposit in Sberbank of the Russian Federation.
With a statement of acceptance of the inheritance to the notary addressed: the wife of the deceased - Victoria Leontyeva; the mother of the deceased is Nadezhda Leontyeva, 65, who lives separately from him, but is dependent on him; father of the first wife of the deceased - Stepan Sotnikov, 70 years old, who lived with him after the divorce from his daughter for 2 years before the testator’s death and was fully dependent on him; the wife of the deceased’s first marriage, Lyubov Leontyeva, with whom he paid child support for the child within two years from the date the child was born until her death; sister of the deceased - Anastasia Alferova, 50 years old; the aunt of the deceased - Galina Galkina, 70 years old.
Which of these persons should be called upon to inherit the property of Leonard Leontiev?
What line of heirs should be called upon to be inherited, since Leonard Leontiev did not make a will?
Which of these persons are mandatory heirs?
Is Leonard Leontyev´s child from the first marriage the heir? Who is entitled to apply for accepting an inheritance on his behalf?