A 4-bit D/A converter is connected to a free-running 3-bit UP counter, as shown in the following figure. Which of the following waveforms will be observed at V₀=?

In the figure shown above, the ground has been shown by the symbol $$\nabla $$

Two D-flip-flops, as shown below, are to be connected as a synchronous counter that goes through the following Q₁Q₀ sequence $$00 \to 01 \to 11 \to 10 \to 00 \to ......$$
The inputs D₀ and D₁ respectively should be connected as

The point p in the following figure is stuck- at-1. The output f will be

The number of product terms in the minimized sum-of-product expression obtained through the following k-map is ( where , "d" denotes don't care states)