A uniform disc with mass M = 4 kg and radius R = 10 cm is mounted on a fixed horizontal axle as shown in figure. A block with mass m = 2 kg hangs from a massless cord that is wrapped around the rim of the disc. During the fall of the block, the cord does not slip and there is no friction at the axle. The tension in the cord is ____________ N.

(Take g = 10 ms^$$-$$2)

A car covers AB distance with first one-third at velocity v₁ ms^$$-$$1, second one-third at v₂ ms^$$-$$1 and last one-third at v₃ ms^$$-$$1. If v₃ = 3v₁, v₂ = 2v₁ and v₁ = 11 ms^$$-$$1 then the average velocity of the car is _____________ ms^$$-$$1.