In a lab experiment, the decay of a radioactive isotope is being observed. At the beginning of the first day of the experiment the mass of the substance was 200 grams and mass was decreasing by 11% per day. Determine the mass of the radioactive sample at the beginning of the 10th day of the experiment. Round to the nearest tenth (if necessary).

The correct answer is - 62.36 g.

Explanation:

Given:

Mass of substance - 200

decreasing rate - 11% per day

mass at the beginning of the 10th day - ?

Solution:

F(x) = 200*(1 - 11)^x

here x the time

F(x) = 200* (0.89)^10

= 200*0.3118

= 62.3634

Thus, the correct answer is 62.36 g.

hey there!

mass = 6.75 g

volume =   9 cm³

therefore:

d = mass / volume

d   = 6.75 / 9

d = 0.7 g/cm³

answer b

the objects have the same charge is correct.

nathan lee