The radioactive substance cesium-137 has a half-life of
30
years. the amount
at
(in grams) of a sample of cesium-137 remaining after
t
years is given by the following exponential function.

Solve the given system of equations. 2y= -x+9 , 3x-6= -15

The point a is at –2 and the point b is at 7. marissa would like to divide this line segment in a 4: 3 ratio, and she would like to use the formula x = (x2 – x1) + x1. what values should she substitute into the formula? a = a + b = x1 = x2 =

The distribution of a sample of the outside diameters of pvc pipes approximates a symmetrical, bell-shaped distribution. the arithmetic mean is 14.0 inches, and the standard deviation is 0.1 inches. about 68% of the outside diameters lie between what two amounts?