Answer:
New net worth to three significant figures = $80.2 billion
Dollars are given to charity = $100,250,000
Explanation:
Net worth = $77.0 billion
stock Gains = $3.20 billion
New net worth = $77.0 billion + $3.20 billion = $80.20 billion
New net worth to three significant figures = $80.2 billion
One-eighth of a percent = (1/8 x 1) / 100 = 0.00125
Dollars are given to charity = 0.00125 X $80.2 billion = $100,250,000
Or
$80,200,000,000/100 = $802,000,000
Answer:
We could do two 1:50 dilutions and one 1:4 dilutions.
Explanation:
Hi there!
A solution that is 1000 ug/ ml (or 1000 mg / l) is 1000 ppm.
Knowing that 1 ppm = 1000 ppb, 100 ppb is 0.1 ppm.
Then, we have to dilute the stock solution (1000 ppm / 0.1 ppm) 10000 times.
We could do two 1:50 dilutions and one 1:4 dilutions (50 · 50 · 4 = 10000). Since the first dilution is 1:50, you will use the smallest quantity of the stock solution (if we use the 10.00 ml flask):
First step (1:50 dilution):
Take 0.2 ml of the stock solution using the third dispenser (20 - 200 ul), and pour it in the 10.00 ml flask. Fill with water to the mark (concentration : 1000 ppm / 50 = 20 ppm).
Step 2 (1:50 dilution):
Take 0.2 ml of the solution made in step 1 and pour it in another 10.00 ml flask. Fill with water to the mark. Concentration 20 ppm/ 50 = 0.4 ppm)
Step 3 (1:4 dilution):
Take 2.5 ml of the solution made in step 3 (using the first dispenser 1 - 5 ml) and pour it in a 10.00 ml flask. Fill with water to the mark. Concentration 0.4 ppm / 4 = 0.1 ppm = 100 ppb.
Answer:
5.61983 × 10^5
Explanation:
Move the decimal forward 5 spaces, each time doing so you add 10^(# of spaces moved, in this case 5)
