Bonjour,
A= 65×10³× (10-5) / (26 ×10²)
A = 65 000 × (5 / 2600)
A = 65 000 × 1/520
A = 125
A = 1,25×10²
B= 153×10⁻⁴ + 32 ×10⁻³ -16×10⁻⁵
B = 0,0153 + 0,032 - 0,00016
B = 0,04714
B = 4,714×10⁻²
C= 1,6 ×10^-12 sur 4× 10-9
C = 0.0000000000016 / 0.000000004
C ≈ 0.0004
C = 4×10⁻⁴
D = (0,3×10² ×5×10⁻³) sur (4×10⁻⁴)
D = (30 × 0,005) / (0,004)
D = 37,5
D = 3,75×10¹