You give a 4.90 kg box a hard shove at the bottom of a ramp, and it leaves your hand with a speed of 7.00 m/s. The ramp is inclined at an angle of 30.0^o, and the coefficient of kinetic friction between the ramp and the box is 0.450. The box slides up the ramp and eventually stops. What is the magnitude of the acceleration of the box while it is sliding up the ramp?

9.31 m/s² 24.8 m/s² 42.7 m/s² 8.72 m/s²