A research student is working with a culture of bacteria that doubles in size every 90 minutes. The initial population count was 1225 bacteria. Rounding to five decimal places, write an exponential function, \( P(t)=P_{0} e^{k t} \), representing this situation. To the nearest whole number, what is the population size after 5 hours?

Clearly indicate all intercepts with the axes as well as the QUESTION 7 Given the function with the equation \( k(x)=\frac{-6}{x+2}-2 \) : 7.1 Write the equations of the asymptotes of \( k \). 7.2 Give the range of \( k \). 7.3 Give the domain of \( k \).

If \( (-1,8) \) is a point on the graph of \( y=f(x) \), which of the following must be on the graph of \( y=f(-x) \) ? \( (8,1) \) \( (-1,-8) \) Choose the correct answer below. \( (1,8) \) \( (-8,-1) \)

(a) Express the distance \( d \) from \( P \) to the origin as a function of \( x \). \( d(x)=\sqrt{\mathrm{x}^{4}-3 \mathrm{x}^{2}+4} \) (Simplify your answer. Type an exact answer, using radicals as needed.) (b) What is \( d \) if \( x=0 \) ? If \( x=0 \), the distance \( d \) is (Type an integer or decimal rounded to two decimal places as needed.)

Let \( P=(x, y) \) be a point on the graph of \( y=x^{2}-2 \). Complete parts (a) through (e) below. (a) Express the distance \( d \) from \( P \) to the origin as a function of \( x \). \( d(x)= \) (Simplify your answer. Type an exact answer, using radicals as needed.)

(a) Express the distance \( d \) from \( P \) to the origin as a function of \( x \). \( d(x)=\sqrt{x^{4}-3 x^{2}+4} \) (Simplify your answer. Type an exact answer, using radicals as needed.) (b) What is \( d \) if \( x=0 \) ? If \( x=0 \), the distance \( d \) is 2 . (Type an integer or decimal rounded to two decimal placels as needed.) (c) What is \( d \) if \( x=1 \) ? If \( x=1 \), the distance \( d \) is \( \square \). (Type an integer or decimal rounded to two decimal places as needed.)