Which answer choice shows the simplified version of this expression? (5a^4)(4a^3)

Answer choices:

20a^12
9a^7
20a^7
9a^12

When you dilate a figure with a scale factor of 1/2, what will the dilated figure look like?                                                                                           a: the dilated figure will have side lengths that are half the length of the original side lengths.                                                                          b: the angles in the dilated figure will be half the measure of the original figure.                                                                                c: the dilated figure will have side lengths twice the length of the original.