In a public opinion survey, 70 out of a sample of 100 high-income voters and 55 out of a sample of 80 low-income voters supported the introduction of a new national security tax. a/ Estimate, with 95% confidence level, the true proportion of high-income people who will vote for the introduction of the tax.
b/ Can we conclude at the 5% level of significance that the proportion favoring the new security tax differs between high-income and low-income voters?

it is contrapositive

i could not see the question too well so check yourself again too . this is because i want you to get it correct.

answer: the answer is e

step-by-step explanation:

the solution of the equation is 2.23 ⇒ answer b

step-by-step explanation:

* lets revise the meaning of exponential function

- the form of the exponential function is y = ab^x, where a ≠ 0, b > 0 ,  

  b ≠ 1, and x is any real number

- it has a constant base b

- it has a variable exponent x

- to solve an exponential equation, take the log or ln of both sides,  

  and solve for the variable

* lets solve the problem

∵

- the base is 7 and the exponent is x

- insert ㏑ in both sides

∴

- use the rule

∴ x ㏑(7) = ㏑(77)

- to find x divide both sides by ㏑(7)

∴

* the solution of the equation is 2.23 to the nearest 2 decimal places