Sean is conducting an experiment with an isotope of a particular element that has a half-life of 4 hours. he begins with a sample of the isotope with a mass of 92 grams. he then measures the mass of the object every hour. what is the approximate mass of the sample after 20 hours?

the arc length is found by finding the circumference of the full circle (2xpixradius) and then dividing by 4 to find just one quarter of the circle (90 degrees).

b

step-by-step explanation:

the equation of a line in point- slope form is

y - b = m(x - a)

where m is the slope and (a, b) a point on the line

calculate m using the slope formula

m = (y₂ - y₁ ) / (x₂ - x₁ )

with (x₁, y₁ ) = (0, 4) and (x₂, y₂ ) = (3, - 5) ← 2 points on the line

m = = = - 3

with m = - 3 and (a, b) = (3, - 5), then

y - (- 5) = - 3(x - 3), that is

y + 5 = - 3(x - 3) → b

think the answer is 30 degrees. if not than it is 20 degrees. not 100% sure. let me know if it was right.

gill russ