One of the nuclides in spent nuclear fuel is U-235, an alpha emitter with a half-life of 703 million years. How long will it take for an amount of U-235 to reach 24.0% of its initial amount? Express your answer in years to three significant figures. View Available Hint(s)

1447584654 years or 1.44 billion years

Explanation:

From the formula;

0.693/t1/2=2.303/t log No/N

Where;

t1/2 = half life of the U-235 nuclides

No= amount of U-235 initially present

N= amount of U-235 present after a time t

t= time taken for N amount of U-235 to remain

Since N= 0.24No

Substituting values

0.693/703×10^6 = 2.303/t log No/0.24No

9.8578×10^-10 = 2.303/t log 1/0.24

9.8578×10^-10 = 1.427/t

t= 1.427/9.8578×10^-10

t= 1447584654 years

under a microscope, cancer cells may look very different from normal cells. they often have different sizes and some may be larger than normal while others are smaller. cancer cells are often abnormally shaped and the control centre of the cell (the nucleus) may have an abnormal appearance.

i think? ?

a) the particles of the chair are strongly held together.