Please HELP!!!

The environmental protection agency allows 10 ppb concentration of arsenic in drinking water. If an 8 oz glass of water is at 10 ppb, how many ug of arsenic (As) is present? (8 oz= 236mL)

represent the system of equations in augmented matrix form y= 1/4x -3 y=-3x +5

The diameters of four different types of atoms are given below. Atom A: 1.35 * 10^-7 mm; Atom B: 1.80 * 10^-7 mm; Atom C: 6.00 * 10^-8 mm; Atom D: 2.50 * 10^-8 mm What is the order of these atoms from largest to smallest? (1 point) A. B;A;C;D B. C;D;B;A C...

What order of 1.5 * 10^3, 1.4 *10^-1, 2 * 10^3, and 1.4 *10^-2 from least to greatest? (1 point) A. D<B<A<C B. C<A<B<D C. D<B<C<A D. B<D<A<C

I know that WWII and the holocaust are definietly completely different things I don't know about your second questions though...

thank you!