Need help and I need it fast plz

Country carpets charges $22 per square yard for carpeting, and an additional installation fee of $100. city carpets charges $25 per square yard for the same carpeting, and an additional installation fee of $70

An objects motion is described by the equation d= 4sin (pi t) what will the height of the object be at 1.75 seconds?

If 2(a^2+b^2)=(a+b)^2 then, > a+b=0, > ab=0, > a=b, > 2a=b