There  are  two  cylinder-shaped  wooden  billets,  each  having  a  mass  of  45  kg,  in  a  vertical  wall  sewage,  which  contains  water  in  it.  The two billets have the same size and the same uniform material; they touch each other  and  the  walls  of  the  sewage.  One  of  them  is  just totally  under  the water,  whilst  only  half  of  the  other  one  is  immersed  into  the  water. Friction  is  negligible  everywhere.  (density  of  water  is  1000 kg/m3 and  g = 10 m/s2). Choose the correct option(s)