Technically speaking, yes you can. Using a microscope though.
Answer:
The right answer is "3 g".
Explanation:
Given:
Initial mass substance,

By using the relation between half lives and amount of substances will be:
⇒ 


Thus, the above is the correct answer.
<span>The right answer is D. In a situation where the sound wave reaches the ear and the reflected wave reaches the ear less than 0.1 seconds later, the individual would not be able to hear an echo. There needs to a far more significant delay between the sound and the reflection of said sound reaching the listener's ear for the echo effect to become apparent.</span>
Always remember that pH + pOH = 14
Here, you have a pOH of 11.24, so you replace it in the equation, and u get:
pH + 11.24 = 14
Then, You move 11.24 to the other part. and moving from a part to another change the sign of the equation. And you get:
pH = 14 - 11.24 = 2.76
So, the pH of a solution that has a pOH of 11.24 is pH = 2.76
Hope this Helps :)