### Question:
GeoJsonLineString extends LineString { public List<Double> getAltitudes() { return mAltitudes; } GeoJsonLineString(List<LatLng> coordinates);  GeoJsonLineString(List<LatLng> coordinates, List<Double> altitudes); String getType(); List<LatLng> getCoordinates(); List<Double> getAltitudes();  }### Answer:
@Test public void testGetAltitudes() { List<LatLng> coordinates = new ArrayList<>(); coordinates.add(new LatLng(0, 0)); coordinates.add(new LatLng(50, 50)); coordinates.add(new LatLng(100, 100)); List<Double> altitudes = new ArrayList<>(); altitudes.add(100d); altitudes.add(200d); altitudes.add(300d); ls = new GeoJsonLineString(coordinates, altitudes); assertEquals(altitudes, ls.getAltitudes()); assertEquals(ls.getAltitudes().get(0), 100.0, 0); assertEquals(ls.getAltitudes().get(1), 200.0, 0); assertEquals(ls.getAltitudes().get(2), 300.0, 0); }