The final mass after decay can be obtained by using under given relation:
half life period of As-81 = 33 seconds
mf = mi x (1/2^n)
= 100 x ( 1/2^(43.2/33))
= 40.4 %
Our values can be defined like this,



The problem can be solved for part A, through the Work Theorem that says the following,

Where
KE = Kinetic energy,
Given things like that and replacing we have that the work is given by
W = Fd
and kinetic energy by

So,

Clearing F,

Replacing the values


B) The work done by the wall is zero since there was no displacement of the wall, that is d = 0.
Answer:
47.4 m
Explanation:
When an object is thrown upward, it rises up, it reaches its maximum height, and then it goes down. The time at which it reaches its maximum height is half the total time of flight.
In this case, the time of flight is 6.22 s, so the time the ball takes to reach the maximum height is

Now we consider only the downward motion of the ball: it is a free fall motion, so we can find the vertical displacement by using the suvat equation

where
s is the vertical displacement
u = 0 is the initial velocity
t = 3.11 s is the time
is the acceleration of gravity (taking downward as positive direction)
Solving the formula, we find

Answer:
I will but can you just wait for some minutes cus I am in a hurry now.
sorry that pic is a little blurry
The minimum number of tickets that could admit all of them is six (6).
This thing is impossible to explain in words, so I shall attempt it with a diagram:
Here are the six ladies:
( A ) ( B )
| |
| |
( C ) ( D )
| |
| |
( E ) ( F )
-- 'E' and 'F' are the daughters of 'C' and 'D' .
-- 'C' and 'D' are the daughters of 'A' and 'B' .
So look what we have now:
-- 'A' and 'B' are the mothers of 'C' and 'D' .
There's 2 of the mothers.
-- 'C' and 'D' are the mothers of 'E' and 'F' .
There's the OTHER 2 mothers.
-- 'A' and 'B' are the grandmothers of 'E' and 'F' .
There's the 2 grandmothers.
-- 'E' and 'F' are the daughters of 'C' and 'D' .
There's 2 of the daughters.
-- 'C' and 'D' are the daughters of 'A' and 'B' .
There's the OTHER 2 daughters.
You want to know what ? !
The group is even bigger than THAT.
There are also 2 GRAND-daughters in the family ... 'E' and 'F' .
So now you have a list of 12 people ! ... 4 mothers, 2 grandmothers,
4 daughters, and 2 grand-daughters ... and they all get in to the
Christmas Market with only six tickets. Legally !
Such a deal !
Don't forget : Christmas this year is also the first day of Chanukah !
All for the same price !