Discover answers to your most pressing questions at Westonci.ca, the ultimate Q&A platform that connects you with expert solutions. Get expert answers to your questions quickly and accurately from our dedicated community of professionals. Explore comprehensive solutions to your questions from knowledgeable professionals across various fields on our platform.

Certain radioactive material decays in such a way that the mass remaining after [tex]t[/tex] years is given by the function

[tex]m(t) = 330e^{-0.03t}[/tex]

where [tex]m(t)[/tex] is measured in grams.

(a) Find the mass at time [tex]t = 0[/tex].
Your answer is:

(b) How much of the mass remains after 20 years?
Your answer is:

Round answers to 1 decimal place.


Sagot :

Certainly! Let's solve this step-by-step:

The given function representing the mass remaining after [tex]\( t \)[/tex] years is:
[tex]\[ m(t) = 330e^{-0.03t} \][/tex]
where [tex]\( m(t) \)[/tex] is in grams.

### Part (a): Find the mass at time [tex]\( t = 0 \)[/tex]

To find the mass at time [tex]\( t = 0 \)[/tex], substitute [tex]\( t = 0 \)[/tex] into the given function:

[tex]\[ m(0) = 330e^{-0.03 \cdot 0} \][/tex]

Since any number raised to the power of 0 is 1:

[tex]\[ m(0) = 330e^0 \][/tex]
[tex]\[ m(0) = 330 \times 1 \][/tex]
[tex]\[ m(0) = 330 \][/tex]

So, the mass at time [tex]\( t = 0 \)[/tex] is:
[tex]\[ \boxed{330.0 \text{ grams}} \][/tex]

### Part (b): How much of the mass remains after 20 years?

To determine the mass remaining after 20 years, substitute [tex]\( t = 20 \)[/tex] into the function:

[tex]\[ m(20) = 330e^{-0.03 \cdot 20} \][/tex]

Let's simplify the exponent first:

[tex]\[ -0.03 \cdot 20 = -0.6 \][/tex]

Now, substitute back into the equation:

[tex]\[ m(20) = 330e^{-0.6} \][/tex]

By evaluating [tex]\( e^{-0.6} \)[/tex] and then multiplying by 330, we find:

[tex]\[ m(20) \approx 181.1 \][/tex]

So, the mass after 20 years is:
[tex]\[ \boxed{181.1 \text{ grams}} \][/tex]

### Summary:
- (a) The mass at time [tex]\( t = 0 \)[/tex] is [tex]\( 330.0 \)[/tex] grams.
- (b) The mass remaining after 20 years is [tex]\( 181.1 \)[/tex] grams.

Both answers have been rounded to 1 decimal place as required.