Question

Need help!!
Polluted water flows into a pond. The concentration of pollutant,c, in the pond at time t minutes is modelled by the equation c(t)= 9-90000(1/10000+3t), where c is measured in kilograms per cubic metre.
a) When will the concentration of pollutant in the pond reach 6kg/m^3?
b) What will happen to the concentration of pollutant over time?

Answer 1

for a, set the c(t) equation equal to 6kg/m^3 and solve for t

Answer 2

Think about the problem with regards to that answer and you should get b

Answer 3

ok thnx

Answer 4

can you plz help me with more question

Answer 5

Sure thing, let me know if you need help

Answer 6

just tell me that i have to do

Answer 7

Tayla purchased a large box of comic books for $300. She gave 15 of
the comic books to her brother and then sold the rest on an Internet
website for $330, making a profit of $1.50 on each one. How many
comic books were in the box? What was the original price of each
comic book?

Answer 8

how can i solve this question

Answer 9

ok so when I divide 330 by 1.5 I get 220

Answer 10

but its wrong

Answer 11

i am not getting the same answer

Answer 12

oh weird, thats the only way i can think to do it, sorry

Answer 13

Tayla purchased a large box of comic books for $300.

She gave 15 of the comic books to her brother
and then sold the rest on for $330,

making a profit of $1.50 on each one.

How many comic books were in the box?
n =15 + 330/(1.50)

What was the original price of each comic book?
300/n

Answer 14

this of course assumes that the value of each individual comic was the same thruout ... otherwise theres no real way to tell how much each one was.