the star named sirius has a declination of approximately -16°. in what direction is sirius located from the celestial equator?
east
west
north
south

Negative celestial declinations are all positions in the sky that are directly over south surface latitudes.

Sirius is SOUTH of the celestial equator.

During the course of a year, it traces a circular path directly over the parallel of 16° South latitude, taking it over Peru, La Paz in Bolivia, St. Helena island in the Atlantic, Namibia, Angola, Zambia, Mozambique, Malawi, Madagascar, Australia, French Polynesia, American Samoa, and the Pacific Ocean.

wavelength divides in half and speed stays the same.