The acceleration of block A is 0.6 m/s².
The net force on the blocks is determined by applying Newton's second law of motion.
∑F = ma
The acceleration of block A is calculated by applying Newton's second law of motion as follows;
[tex]F_a + F_b = F\\\\F_a = F-F_b\\\\m_a a_a = F- m_ba_b\\\\a_a = \frac{F- m_ba_b}{m_a}[/tex]
Where;
[tex]a_a = \frac{12\ - \ 6 \times 1.8}{2} \\\\a_a = 0.6 \ m/s^2[/tex]
Thus, the acceleration of block A is 0.6 m/s².
Learn more about Newton's second law of motion here: https://brainly.com/question/3999427