Answer:
1
Step-by-step explanation:
The amplitude is the maximum distance away from the middle of the wave. Here we can see that the middle of the wave is the x axis and the farthest point (largest difference between the y coordinate of the x-axis, or the line y = 0, and the wave) is 1 unit away.
Answer:
3x + 30
Step-by-step explanation:

3x + 30 would be an equivalent expression.
Hope this helps.
Answer:
1.25
Step-by-step explanation:
10/4=2.5
2.5*0.5
Answer:
40%
Step-by-step explanation:
Percent means out of 100
Multiply the top and bottom by 20 to get the bottom to 100
2/5 * 20/20 = 40/100
The percent is 40%