Помогите пожалуйста!!)))

2. =-0,4*10000+3*100-98=
=-4000+300-98=-3798
3. =2,4/(-2,4)=-1
4.
$= ( \frac{8 \times 2}{38} - \frac{17}{38} ) \times \frac{19}{5} = \\ = ( \frac{16 - 17}{38} ) \times \frac{19}{25} = \\ - \frac{1}{38} \times \frac{19}{5} = \\ = - \frac{1}{2} \times \frac{1}{5} = - \frac{1}{10} = - 0.1$
5.
$= {2}^{2} \times {10}^{6} \times \frac{12}{ {10}^{3} } = \\ = \frac{4 \times {10}^{6} \times 12}{ {10}^{3} } = \\ = 48 \times {10}^{3} = 48 \times 1000 = \\ = 48000$