With an expression like this, you have to raise all the terms to the 3rd power. So the 5 will become
,
will become
, the 4 will become
and finally, the
becomes
. If you place all of these together in the same fraction, the new answer equivalent to the initial expression is
2.5 x 10 = 25 m^2
1.5 x 10 = 15 m^2
2 x 10 = 20 m^2
0.5 x 1.5 x 2 = 1.5 m^2 (2 times)
Total = 63 m^2
So just fill in 63.
To simplify the problem imagine the half-life was 2.5 minutes. This means that there would be 10/2.5=4 periods of halving the mass, which means 1/2⁴=1/16 of 18g=1.125g.
So for the given half-life we calculate 10/2.552=3.9185 approx. So we now find 2 to this power=15.1211 approx and divide into 18=1.19g. This is close to the rough estimate we did earlier.
10.5 and 8.4 ......................,,,,,
Answer:
5(9+6)
5×9=45
5×6=30
I hope this is good enough:
