To draw vector diagrams for the given sums, we need to follow the vector addition principles. Here's the explanation for each part:

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a. Sum of 𝑎 + 𝑏⃗ and (𝑎 + 𝑏⃗) + 𝑐

1. 𝑎 + 𝑏⃗: To represent the sum of vectors 𝑎 and 𝑏⃗, place the tail of vector 𝑏⃗ at the head of vector 𝑎 (or vice versa), then draw the resultant vector from the tail of 𝑎 to the head of 𝑏⃗. This vector represents 𝑎 + 𝑏⃗.

2. (𝑎 + 𝑏⃗) + 𝑐: Now, take the resultant of 𝑎 + 𝑏⃗ and add the vector 𝑐. To do this, place the tail of vector 𝑐 at the head of the resultant vector 𝑎 + 𝑏⃗. Draw the resultant vector from the tail of 𝑎 to the head of 𝑎 + 𝑏⃗ + 𝑐.

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b. Sum of 𝑏⃗ + 𝑐 and 𝑎 + (𝑏⃗ + 𝑐)

1. 𝑏⃗ + 𝑐: Place the tail of vector 𝑐 at the head of vector 𝑏⃗, and the resultant vector will go from the tail of 𝑏⃗ to the head of 𝑐. This vector represents 𝑏⃗ + 𝑐.

2. 𝑎 + (𝑏⃗ + 𝑐): Now, take the vector 𝑎 and add the resultant of 𝑏⃗ + 𝑐. Place the tail of vector 𝑎 at the tail of the resultant vector 𝑏⃗ + 𝑐, and then draw the resultant vector from the tail of 𝑎 to the head of 𝑎 + (𝑏⃗ + 𝑐).

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I can generate vector diagrams for you if you'd like to visualize these sums! Would you like me to do that?