Please help me with these 2 problems!

Question

1. Complete the table for the time t necessary for P dollars to triple if interest is compounded continuously at rate r.

r= 2%, t=?
r= 4%, t=?
r= 6%. t=?
r= 8%, t=?
r= 10%, t=?
r= 12%, t=?

2. Draw a scatter plot of the data in the above exercise. Use the regression feature of a graphing utility to find a model for the data.

^^I have no clue what the regression feature is.

Answer 1

1. To get the values of t you will need for your table, solve the equation
(1+r)^t = 3.00
Hint: use logs.
For r = 6%
(1.06)^t = 3
t = log 3/log 1.06 = 18.85 years

2. I don't have a graphing calculator/utility. There might be some online application you can use. The product of r and the tripling time will be nearly a constant. You should try fitting a relation
t = constant/r, instead of a straight-line fit.

Answer 2

2% - 54.93
4% - 27.47
6% - 18.31
8% - 13.73
10% - 10.99
12% - 9.16

Answer 3

2% = 68
4% = 56
6% = 49
8% = 38
10% = 29
12% = 16