Answer:
a) 6x10^-6 b) 0.000006 c) I would not be concerned
Explanation:
a)
50% is just half and more just means added onto.
Half of 4x10^-6 is 2x10^-6
If you add that onto the original value, you will have:
6x10^-6 (standard form)
b)
0.000006 (ordinary number)
c)
I would not be concerned about the increase in probability of a side effect while using the new medicine. The probability to begin with is extremely low, almost insignificant. While the 50% increase may sound intimidating, it is just a 50% increase on a number that is already very very small. Honestly, it makes almost no difference.