The sum of numbers or expression involves adding the expressions and the numbers together.
Assume that the sum of the degrees is given as:

The above sum can be rewritten as:

Take the sum of all the numbers (including -2 in bracket)

If the sum of the degrees is given as
, then the number of years he worked would be 6
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Answer:
Do I do the answer in standard form or the question #
D.........................................
Hello,
26.
period=4
max=3
min=-3
27:
p=8
max=5
min=0
28:
p=8
max= 4 (twice)
min=-4 (twice)