Combine like terms.
4a + b + a
a.
4a + 4b
b.
5a + 5b
c.
5a + b
d.
4ab

To combine these terms you would add up the a's and b's.
4a+b+a is the same as 4a+a+b. Anything without a constant in front has a value of 1. You have 4a's and you need to add another a. That equals 5a's. The b is left alone since you can only add like variables.
The answer would be C) 5a +b

The answer is the numbers between =5 and 5

Period is the time it takes for one “cycle” to complete. in the parent sine function, period is 2*pi since sin(0) = 0, sin(pi/2) = 1, sin(pi) = 0, sin(3pi/2) = -1, and sin(2pi) = 0. at that point, the sequence repeats itself. i’m not sure if your graph is similar to the sine function since you didn’t provide a picture, but you can find the period by looking at a graph.