The population of the world¹ t years after 2010 is predicted to be P = Round your answers to one decimal place. (a) What population is predicted in 2026? The predicted population of the world in the year 2026 is i (b) What is the predicted average population between 2010 and 2026? The average population of the world over this time period is i 6.77e0.0121 billion. billion people. billion people.

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A certificate of deposit is worth P (1+r)t dollars after t years, where r is the annual interest rate expressed as a decimal, and P is the amount initially deposited. Which investment will be worth more? Investment A, in which P =$7300, r=4%, and t=5 years.  Or investment B, in which P= $6300, r=6%, and t= 7years. Round to two decimal places. The value of certificate A will be what? And the value for investment B will be what? And which is worth more, A or B?

A certain city's power company charges their residents for electricity usage on a daily basis. There is a basic charge of 11.57 cents. For each day the first 10 kWh cost 4.81 cents per kWh and any additional kWhs are 9.69 per kWh. (A kWh, or kilowatt-hour, is a unit of energy.) (a) Complete the following table using the information provided above. kWhkWh 0 5 10 15 20 cost (dollars)cost (dollars)           kWhkWh 25 30 35 40 cost (dollars)cost (dollars)         (b) We can define a piecewise function f(x)f(x) where xx is the kWh used in a day and f(x)f(x) is the cost, in dollars. This function would have the form   f(x)={g(x)h(x)ififx∈Ax∈Bf(x)={g(x)ifx∈Ah(x)ifx∈B What functions g(x)g(x) and h(x)h(x) make up the piecewise function f(x)f(x)? g(x)=g(x)= for A = h(x)=h(x)= for B = Hint: A and B are intervals. If an interval uses ±∞±∞ write inf or -inf . (c) Using the above function, what is the cost of 26 kWh? dollars. (d) For 3 dollars, what is the maximum kWh usage for one…