the half-life of tritium, or hydrogen-3, is 12.32 years. after about 37 years, how much of a sample of tritium will remain unchanged? a)1/8    b)1/4  c)1/3  d)1/2

What is the composition, in atom percent, of an alloy that consists of 4.5 wt% pb and 95.5 wt% sn? the atomic weights for pb and sn are 207.19 g/mol and 118.71 g/mol, respectively.(a) 2.6 at% pb and 97.4 at% sn(b) 7.6 at% pb and 92.4 at% sn(c)97.4 at% pb and 2.6 at% sn(d) 92.4 at% pb and 7.6 at% sn

Naoki's bicycle has a mass of 10 kg. if naoki sits on her bicycle and starts pedaling with a force of 168 n, causing an acceleration of 2.8 m/s2, what is naoki's mass?

In the space, show a correct numerical setup for calculating the number of moles of co2 present in 11 grams of co2