a)
$$5,31 * 10 = 53,1$$
$$0,23 * 10 = 2,3$$
$$4,3 * 10 = 43$$
$$0,1 * 10 = 1$$
$$0,02 * 10 = 0,2$$
б)
$$5,431 * 100 = 543,1$$
$$30,45 * 100 = 3045$$
$$0,009 * 100 = 0,9$$
$$0,24 * 100 = 24$$
$$0,1 * 100 = 10$$
$$0,02 * 100 = 2$$
в)
$$78,71 * 1000 = 78710$$
$$5,4 * 1000 = 5400$$
$$0,00039 * 1000 = 0,39$$
$$0,009 * 10000 = 90$$
$$0,203 * 10000 = 2030$$