4.
[tex]a) \ m = 2 \ kg, \ \ a = 8\frac{m}{s^{2}}\\\\F = m\cdot a = 2 \ kg\cdot8\frac{m}{s^{2}} = \boxed{16 \ N}\\\\\\b) \ m = 500 \ g = 0,5 \ kg, \ \ a = 30\frac{m}{s^{2}}\\\\F = m\cdot a = 0,5 \ kg\cdot30\frac{m}{s^{2}} = \boxed{15 \ N}\\\\\\c) \ m = 60 \ dag = 0,6 \ kg, \ \ a = 5\frac{m}{s^{2}}\\\\F = m\cdot a = 0,6 \ kg\cdot5\frac{m}{s^{2}} =\boxed{ 3 \ N}[/tex]
[tex]d) \ m = 750 \ g = 0,75 \ kg, \ \ a = 16\frac{m}{s^{2}}\\\\F = m\cdot a = 0,75 \ kg\cdot16\frac{m}{s^{2}}=\boxed{12 \ N}[/tex]
