Staals half
1 gram left
0.3 grams left
half lives are normally written in years
it goes likt this

A=final amount
P=initila amount
t=time elapsed
h=time half life is (same units as time)
let's use days as the units of time
we are given
initial amount=1gram
final amount=0.3gram
time=4 days
so

solve for h

take the ln of both sides


times both sides by h

divide both sides by ln(0.3)

use calculator
h=2.30287
3 sig figs
h=2.303 days
Answer:
k=-j=15
Step-by-step explanation:
See attachment for step by step :)
Answer: $169,500
Step-by-step explanation:
The mean simply means the average price of a set of a numbers that are given. For one t calculate the mean, one has to add the numbers that are given and then divide them by the amount of numbers.
I'm the case above, the numbers given are $165,000, $188,000, $175,000, and $150,000.
Mean = ($165,000 ,+ $188,000 +$175,000 + $150,000) ÷ 4
= $678,000/4
= $169,500
Answer:
Explanation:
Work backward:
1. 2x + 23 = 30
Start:
Multiply the equation by 2:
Subtract 30 from both sides
- 2x - 30 = 7 - 30
- 2x - 30 = -23
Add 23 and 30 to both sides:
2. 3x + 19.5 = 30
Start:
Add 6.5 to both sides:
Multiply by 3:
Distributive property:
3. (10x - 20)/ 5 = 3
Start:
Multiply by 10:
Subtract 20:
Divide by 5:
Answer:
where are the expressions??