Answer:
![-4.728 m/s^(2)](https://img.qammunity.org/2020/formulas/physics/middle-school/reg5nwdovri8tafiuseix3r6ed7r2awvuk.png)
Step-by-step explanation:
F=ma where F is the force, m is the mass of object and a is acceleration
Initial mass is 13000 Kg
Final mass=1300-(66*7)=12538 Kg
where
and
are initial and final mass respectively,
and
are initial and final acceleration respectively
By substitution
![13000* -4.56=12538* a_f](https://img.qammunity.org/2020/formulas/physics/middle-school/a84bmsjeid8h1xg70bxn06decvaxiweluu.png)
![a_f=-4.728026799\approx -4.728 m/s^(2)](https://img.qammunity.org/2020/formulas/physics/middle-school/j9cf8h5sy7ssinbva3wpdngaidwdm97okh.png)