#1**+2 **

The midline of 10 rules out all of the choices except the last two.....

normal period of sin fxn is 2 pi if you divide 'x' by pi/2 you stretch the wave out by a factor of 2 /pi 2 pi * 2/pi =4

so the last one is the correct one

ElectricPavlov Mar 5, 2020