Aculture started with 4,000 bacteria. after 2 hours it grew to 4400 bacteria. predict how many bacteria will be present after 13 hours round your answer to the nearest whole number.

 idk why they want the dratted "k" . it is so simple w/o it ! 
in the form y = ab^x, a = 4000, b = 4400/4000 = 1.1, x = t/2 
N = 4000*1.1^(13/2) = 7432 < 
 
now you won't be satisfied with simplicity, so 
4400 = 4000e^2k 
e^2k = 1.1 
k = ln 1.1/2 = .0477 to 4 dp 
N(13) = 4000e^(13*.0477) = 7436 < 

note that apart from a roundabout way, you get a less accurate ans !

7436

Step-by-step explanation:

y = ab^x

a = 4000

b = 4400/4000 = 1.1

x = t/2 

4400 = 4000e^2k 

e^2k = 1.1 

k = ln 1.1/2 = .0477 to 4 dp 

N(13) = 4000e^(13*.0477) = 7436

costs $3.75? d. Suppose the family had a 10% discount coupon for the entire check and then left an 18% tip. What is the total? Total : Bill -discount + tip Discount.

Step-by-step explanation:

Hope this helps :D