P(-1.69 < z < 1.14) = %D

Cyanide is used in solution to isolate gold in a mine. ¹ This may result in contaminated groundwater near the mine, which needs to be filetered. The following table gives the concentration, c(t) (in parts per million), of cyanide in the groundwater, where t is in years since 2017. 1 www.waterboards.ca.gov, accessed September 16, 2019. t (years) c(t) (ppm) 25.0 21.8 19.01 (a) Find an exponential model for c(t). O i 1 (b) Use the model in part (a) to find the number of years it takes for the cyanide concentration to fall to 11 ppm. Round to three decimal places. 2 (c) The filtering process removing the cyanide is sped up so that the new model is D(t) = c(2t). Find D(t). (d) If the cyanide removal was started three years earlier, but run at the speed of part (a), find a new model, E(t). 1.c (t) = 25(0.872)', D (t) = 25(0.7604)', E (t) = 16.576(0.872)' II. c (t) = 16.576(0.872)', D (t) = 25(0.7604)', E (t) = 25(0.872)' III. c (t) = 16.576(0.7604)', D (t) = 25(0.7604)', E (t) = 25(0.872)'…

After two consecutive years of 7% rates of return, what rate of return in the third year will produce a cumulative gain of 18%? Note: Please make sure your final answer(s) are in percentage form and are accurate to 2 decimal places. For example 34.56%. Rate of return = 0.00 % 0.0 Enter x Cancel

Compute the indicated quantity. P(A) = 0.9, P(B) = 0.3. A and B are independent. Find P(A n B). %3D P(A n B)

3 128 8.8 22.4 2.8 y%3D 5. 27 6. b. 301

9 tab esc Compute. -4.368 3.86 =1 0 14.25 + (-27.381) = Continue q a @ 2 W S e SA 4 d - % f M GS Oll t 6

Test significance of r at the 5% and at the 1%

A=P(1+r/n)^nt   Find A when P=6000​, r=4​%, n=4​, and t=7.

Suppose the price of an airline ticket is $200 plus $0. 10 for each mile traveled. If you spent $256. 60 on airfare between two cities, how many miles are there between the cities? 后 ap區市中 日| [回 うX 8. 土 U N %|||| 豆|頁

For each 1000-foot increase in elevation, how many fewer frost-free days are predicted. We want to determine how many fewer frost-free days are predicted when the elevation increases by 1000 ft.   Predictor  Coef      SE Coef      T              PConstant 316.27     28.31      11.24     0.002Elevation -32.660    3.511    −8.79      0.003S = 11.8603  R-Sq = 95.1% Here, ŷ is the number of frost-free days and the variable x is the elevation measured in thousands of feet. Therefore, each 1000 ft increase in elevation results in a 1 unit increase in x. fill in the blank in part a/part b. a) Recall that the slope of a least-squares line,  ŷ = a + bx, indicates how much ŷ changes when x changes by 1 unit. In part (a), we determined the slope of the line is b = −32.660. This means that for each unit that x increases, the value of ŷ decreases by _______ units. b) Therefore, when the elevation increases by 1000 ft there are _______ fewer frost-free days.