Four blocks are on a horizontal surface. https://www.physicsforums.com/attachment.php?attachmentid=4000&stc=1 randomlabel.png The blocks are connected by thin strings with tensions Tx, Ty, Tz. The masses of the blocks are A=44.0 kg, B=21.0 kg, C=24.0 kg, D=35.0 kg. Two forces, F1=75.0N and F2=51.0N act on the masses as shown. Assume that the friction between the masses and the surface is negligible and calculate the tension Tz.