Answer
The tension in the upper cord is $12.4~N$
The tension in the lower cord is $8.3~N$
Work Step by Step
The tension $T_u$ in the upper cord is equal in magnitude to the component of the total weight of both boxes that is directed down the ramp. We can find this tension:
$T_u = (1.0~kg+2.0~kg)~g~sin~\theta$
$T_u = (1.0~kg+2.0~kg)~(9.80~m/s^2)~sin~25^{\circ}$
$T_u = 12.4~N$
The tension $T_l$ in the lower cord is equal in magnitude to the component of the weight of the 2.0 kg box that is directed down the ramp. We can find this tension:
$T_l = (2.0~kg)~g~sin~\theta$
$T_l = (2.0~kg)~(9.80~m/s^2)~sin~25^{\circ}$
$T_l = 8.3~N$
