17)
Pentru Logan:
[tex]\it v=\dfrac{d}{t} \Rightarrow 50=\dfrac{100}{t} \Rightarrow t=2h[/tex]
Pentru Sandero :
[tex]\it v=\dfrac{d}{t} \Rightarrow 40=\dfrac{d}{2} \Rightarrow d = 40\cdot2 \Rightarrow d = 80 \ km[/tex]
20)
[tex]\it v = 40cm/s,\ \ \ d = 70m=7000cm
\\\;\\
v = \dfrac{d}{t} \Rightarrow 40 = \dfrac{7000}{t} \Rightarrow 40\cdot t = 7000 \Rightarrow t = 7000:40 =175\ s[/tex]
27)
[tex]\it \rho =\dfrac{m}{V} \Rightarrow m = \rho\cdot V = 50\cdot900 = 45000\ kg = 45\ t[/tex]
