Three blocks of masses ${\mathrm{m}}_1,{\mathrm{m}}_2$ and ${\mathrm{m}}_3$ are connected by massless strings as shown on a frictionless table. They are pulled with a force ${\mathrm{T}}_3=40\mathrm{N}$ If ${\mathrm{m}}_1=10\mathrm{kg},{\mathrm{m}}_2=6\mathrm{kg}$ and $m_3=4\mathrm{kg}$ the tension ${\mathrm{T}}_2$ will be