Please Help Us Prepare For The Semester Exam!!!! Part 2

This is the part 2 of our study guide.

Solve the equation.

1. 2.7^x = 4

2. ln x - ln(3x - 5) = 2

3. The number of redwood saplings in a forested study area has been determined to be approximated by the function:

N(t) = 720/1 + 19e^(0.15t)

when t is the time (in years) after the study was begun.

a. What was the initial number of saplings?

b. When will the number of saplings be 370?

c. What is the carrying capacity, the maximum number of saplings possible in the study area?

THANK YOU VERY MUCH WE REALLY APPRECIATE YOUR HELP!!:)

4. The half-life of lead-209 is 3.3 hours. The initial amount S grams.

a. Express the amoundt of substance S remaining as a function of time t.

b. How mmuch of the substance is left after 3.3 hourse? after 33 hours?

c. Determine S if there is 5 g left after 22 hours.