
Amplitutde:

Normally for sinx amplitude is 2 (1 +1). In the case when it is half sine amplitude is halved, therefore 0.5 +0.5 = 1 Paramers alpha = 2x does not matter because it only stretches the graph horizontally.
90° angle on a straight lines gotta be 180°
Answer: 12
Step-by-step explanation: to find perimeter we have to add all the sides of the shape so, for a square you can just simply multiply your given side 3 by 4 because there is 4 sides of a square and this equals to 12.