What is the following difference?<br> 11 inverse 45 -4 inverse 5

A 41 gram sample of a substance that's used to detect explosives has a k-value of 0.1392. Find the substance's half life, in day

-BARSIC- [3]

Answer:

The substance half-life is of 4.98 days.

Step-by-step explanation:

Equation for an amount of a decaying substance:

The equation for the amount of a substance that decay exponentially has the following format:

$A(t) = A(0)e^{-kt}$

In which k is the decay rate, as a decimal.

k-value of 0.1392.

This means that:

$A(t) = A(0)e^{-0.1392t}$

Find the substance's half life, in days.

This is t for which $A(t) = 0.5A(0)$ . So

$A(t) = A(0)e^{-0.1392t}$

$0.5A(0) = A(0)e^{-0.1392t}$

$e^{-0.1392t} = 0.5$

$\ln{e^{-0.1392t}} = \ln{0.5}$

$-0.1392t = \ln{0.5}$

$t = -\frac{\ln{0.5}}{0.1392}$

$t = 4.98$

The substance half-life is of 4.98 days.

5 0

2 years ago

Trigonometry

Nadusha1986 [10]

55° is equal to 0.9599 radians.

Step-by-step explanation:

Step 1:

If an angle is represented in degrees, it will be of the form x°.

If an angle is represented in radians, it will be of the form $\frac{\pi}{x}$ radians.

To convert degrees to radians, we multiply the degree measure by $\frac{\pi}{180}$ .

For the conversion of degrees to radians,

the degrees in radians = (given value in degrees)( $\frac{\pi}{180}$ ).

Step 2:

To convert 50°,

$55\left(\frac{\pi}{180}\right)=\frac{55\pi}{180}.$

$0.3055 (\pi) =0.9599$ radians.

So 55° is equal to 0.9599 radians.

7 0

2 years ago

Read 2 more answers

A seed company planted a floral mosaic of a national flag. The perimeter of the flag is 2,420 ft Determine the flag's width and

ElenaW [278]

The answer is 80ft 140ft

5 0

2 years ago

Katie grew 26 flowers with 13 seed packets. With 55 seed packets, how many total flowers can Katie have in her garden?

Leokris [45]

110 flowers in her garden.

3 0

3 years ago

Read 2 more answers

Mark borrowed $600 at an intrest rate of 8% per year for 4 years. How much simple intrest will he have to pay?

miv72 [106K]

Answer:

He will have to pay $192 in simple interest.

Step-by-step explanation:

This is a simple interest problem.

The simple interest formula is given by:

E = P*I*t

In which E is the interest, P is the principal(the initial amount of money), I is the interest rate(yearly, as a decimal) and t is the time.

In this problem, we have that:

P = 600, r = 0.08, t = 4

So

E = P*I*t = 600*0.08*4 = 192

He will have to pay $192 in simple interest.

6 0

2 years ago

What is the following difference? 11 inverse 45 -4 inverse 5