5. After 6 hours, the concentration is halved. After 12 hours, it will be quartered. If the original concentration is 200 nmol, a quarter is 50 nmol.
14. The population doubles after 3 hours, and a day is 24 hours. That means that the original population should be multiplied by
, or
. 3 million times
is 3 * 256 million, or 768 million.
15. The concentration is halved every 8 hours and the original concentration is 100 nmol. So now, how many times do you halve 100 to get to 12.5?
100/2 = 50, 50/2 = 25, 25/2 = 12.5. That's three times. 3 * 8 is 24 hours, or 1 day.
Answer:
C. 2.5×10^-27
Step-by-step explanation:
(2×10^-13)^-2 = 2^-2 × 10^(13×(-2)) = 1/4 × 10^-26
= 0.25 × 10^-26 = 2.5 × 10^-27
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Your scientific or graphing calculator can compute and display this for you.
Let the cost of one cup of hot chocolate be = x
Let the cost of one cup of hot tea be = y
Paul paid $ 25.50 for 3 cups of hot chocolate and 4 cups of tea.
Equation becomes =
...(1)
As given, the cost of each cup of tea was 2/3 the cost of each cup of hot chocolate.
.... (2)
Putting the value of y from (2) in (1)

=
=
=
x=4.5

=
y =3
Hence each cup of hot chocolate is $4.50
Each cup of tea is $3.
Simple form of the equation y= ax+b
y= (1/7)x + 12
come from 2 equation :
22= 70 a + b
27= 105 a + b