A heterogeneous mixture composes of non- uniform components, so the concrete would be the answer, because you can tell the components from one another.
1. Increasing temperatures and global warming
A new moon
Definition of new moon:
the phase of the moon when it is in conjunction with the sun and invisible from earth, or shortly thereafter when it appears as a slender crescent.
The RNA determine the instructions for a specific trait in an organism, since the DNA cannot leave the nucleus of the cell the RNA then makes a copy of the dna