6x2=12m
6x18=108
12m+108
Simplified: m+9 bc 12/12 and 108/12
Because they both have to do with chemistry
Answer:
- 0.09 % of the original radioactive nucllde its left after 10 half-lives
- It will take 241,100 years for 10 half-lives of plutonium-239 to pass.
Explanation:
The equation for radioactive decay its:
,
where N(t) its quantity of material at time t,
its the initial quantity of material and
its the mean lifetime of the radioactive element.
The half-life
its the time at which the quantity of material its the half of the initial value, so, we can find:

so:




So, after 10 half-lives, we got:




So, we got that a 0.09 % of the original radioactive nucllde its left.
Putonioum-239 has a half-life of 24,110 years. So, 10 half-life will take to pass

It will take 241,100 years for 10 half-lives of plutonium-239 to pass.
Answer: well the time it takes to fall 100m is the same time it takes to travel 65m horizontally.
The time to fall vertically, t is sqrt(2d/g). [this comes from d = 1/2at^2]
so t = sqrt(2*100/9.8) = 4.52s.
The vertical speed at that time is g*t = 9.8*4.52 = 44.3m/s
The horizontal speed is the horizontal distance over the same 4.52s, = 65/4.52 = 14.4m/s.
so the final velocity is = sqrt(44.3^2 + 14.4^2) = 46.6m/s
Explanation: yes