Which of these is a conversion from chemical energy to mechanical energy?

A. A dark light bulb starting to glow

B. A ball rolling down a hill

C. A person lifting a weight

D. A potato being heated in an oven

Ithink it is quantity of plants

The correct answer is "hydrogen".

Replicate prove reliability and validity

It is a mixture. simply put, a compound must be pure, that is, of only one chemical structure and composition. a mixture is made of different chemical substances (i.e. elements, molecules, compounds) that are not chemically bonded to each other, but instead physically grouped together, as in the case of gasoline (a homogeneous solution).