What would life be like if dragons existed

Which of the following is considered to be a vector?               a.  temperature    b.  velocity    c.  time    d.  mass

In a system, when potential energy decreases, then entropy also decreases. true false

Does work output exceed work input when a machine is used? a) yes, it does, as machines create energy. b) it depends on the type of machine used. c) no, it doesn’t, as machines are inefficient. d) no, it doesn’t, as machines cannot create energy.