Contaminated water: In a sample of 43 water specimens taken from a construction site, 23 contained detectable levels of lead. (a) Construct a 99% confidence interval for the proportion of water specimens that contain detectable levels of lead. Round the answer to at least three decimal places.
(b) Construct a 95% confidence interval for the proportion of water specimens that contain detectable levels of lead. Round the answer to at least three decimal places. A 95% confidence interval for the proportion of water specimens that contain detectable levels of lead is

v = 1/3 a^2h

step-by-step explanation:

the volume is 1/3 a^2h.

answer: c, the green line

step-by-step explanation:

there is no black line, eliminate b.

simple interest implies periodic payments, but the red line shows no payments, eliminate d.

simple interest has equal payments. if paid say every day, the graph is about a straight line (actually a stairstep).

the yellow line is not straight, eliminate a.

check: the green line is straight, answer is c.

simple interest with positive interest rate gives a straight line sloping up to the right. green line:

g(t) = $100 + ($200-$100) ÷ (20 years) × (t years)

= $100 + (4%/year) × ($100)(t years)

incidentally, the yellow line curving upward represents continuously compounded interest

y = $100 × 2^(t years / (14 assuming the yellow line hits $200 at 14 years. 2^0 is 1, so y(0) = $100; 2^(14/14) is 2, so y(14) = $200.