What's the triangle symbol called in geometry? is it a delta?

To describe a sequence of transformations that maps triangle abc onto triangle a"b"c", a student starts with a reflection over the x-axis.how should the student complete the sequence of transformations to map triangle abc onto triangle a"b"c"? plz

The actual length of side t is 0.045cm. use the scale drawing to find the actual side length of w

Which container holds more,a half gallon milk jug or a 2 liter juice bottle