For question 16:
first of all attention is a weighted average of the encoder hidden states, so whenever you have the same components in the encoder hidden states, then the result has the same component as well.
So in your version the answer is already [10, 10, ?]
To compute the last component, you have to compute the weights of the average, which are the softmax of the dot-product of encoder by decoder hidden states. In your case the second encoder is only 0.1 higher than the first, thus the second dot-product is simply 0.1*6 higher than the first, which is 140+50+15=250 (thus second is 250.6).
Here the softtmay is of dim 2 so you only have to compute 1 value (well, actually you were provided with some software to do the computation, but it's not really needed): exp(250) / [ exp(250) + exp(250.6) ] = 0.35, thus second is 1-0.35=0.65
And thus the final component you are looking for is 0.35*2.5 + 0.65*2.6 = 2.565