An aqueous solution has a mass of 490 grams
containing 8.5 103 gram of calcium ions. the
concentration of calcium ions in this solution is
(1) 4.3 ppm (3) 17 ppm
(2) 8.5 ppm (4) 34 ppm

This large tectonic plate is bounded on three sides by whats know as the ring of fire. what is the name of this tectonic plate? a) pacific plate b) eurasian plate c) north american plate d) indo- australian plate plz it's science but there's no option for science so i picked chemistry

Why does the sun appear to be the brightest star in the sky? a- its apparent brightness is much greater than other stars. b- it burns more gas, making it brighter than any other star. c- it is the largest star in the galaxy, so it is the brightest star. d- its relative distance to earth is closer than the other stars.

Gwhich r group would most likely be found in a hydrophobic area of the tertiary structure of a globular protein? which r group would most likely be found in a hydrophobic area of the tertiary structure of a globular protein? −ch2−oh −ch2−o||c−nh2 −ch2−coo− −ch2−ch2−ch2−ch2−n+h3