Evaluate the factorial expression. 28! 24

A 30 gram sample of a substance that's used to sterilize surgical instruments has a k-value of 0.1235. Find the substances half

jok3333 [9.3K]

Answer : The substances half life in days is, 5.6 days.

Step-by-step explanation :

Half life : It is defined as the amount of time taken by a radioactive material to decay to half of its original value.

All radioactive decays follow first order kinetics.

The relation between the half-life and rate constant is:

$k=\frac{0.693}{t_{1/2}}$

where,

k = rate constant = 0.1235 per days

$t_{1/2}$ = half-life

Now put all the given values in the above formula, we get:

$0.1235\text {days}^{-1}=\frac{0.693}{t_{1/2}}$

$t_{1/2}=5.6\text{ days}$

Thus, the substances half life in days is, 5.6 days.

5 0

3 years ago

5×1+3×1/10+8×1/100+4×1/1000 write in word form

nydimaria [60]

Answer:

bleh

Step-by-step explanation:

5×1+3×1/10 +8×1/100+4×1/1000 write i dont konw i am just doing this for points

5 0

3 years ago

Read 2 more answers

Two mechanics worked on a car. The first mechanic worked for 5

ArbitrLikvidat [17]

Answer:

$50 and $115

Step-by-step explanation:

We know that,

the sum of the two rates = $165 per hour

Let x and (165 - x) represent the $/hour of the 15hr and 5hr mechanics respectively.

Then combining their charges together to get:

$(x*15)hour+(165-x)*5 hour=1325$

Solving for x to get:

$15x-5x+825=1325$

$10x=500$

$x=50$

So the rate charged per hour by one mechanic is $50 and for the other mechanic = $(165-50)=$ $115.

8 0

3 years ago

Which graph/graphs are proportional? Please hurry!

Paul [167]

I’m 89% sure it’s d
hope it helped :)

3 0

3 years ago

Assume that a company sold 5.75 million motorcycles and 3.5 million cars in the year 2010. The growth in the sale of motorcycles

OverLord2011 [107]

Answer:

Final answer is approx 6.644 years.

Step-by-step explanation:

Given that a company sold 5.75 million motorcycles and 3.5 million cars in the year 2010. The growth in the sale of motorcycles is 16% every year and that of cars is 25% every year.

So we can use growth formula:

$A=P\left(1+r\right)^t$

Then we get equation for motorcycles and cars as:

$A=5.75\left(1+0.16\right)^t$

$A=3.5\left(1+0.25\right)^t$

Now we need to find about when the sale of cars will be more than the sale of motorcycles. So we get:

$3.5\left(1+0.25\right)^t>5.75\left(1+0.16\right)^t$

$3.5\left(1.25\right)^t>5.75\left(1.16\right)^t$

$\frac{\left(1.25\right)^t}{\left(1.16\right)^t}>\frac{5.75}{3.5}$

$\left(\frac{1.25}{1.16}\right)^t>1.64285714286$

$t\cdot\ln\left(\frac{1.25}{1.16}\right)>\ln\left(1.64285714286\right)$

$t>\frac{\ln\left(1.64285714286\right)}{\ln\left(\frac{1.25}{1.16}\right)}$

$t>6.6436473051$

Hence final answer is approx 6.644 years.

7 0

3 years ago