Many cities around the united states are installing led streetlights, in part to combat crime by improving visibility after dusk. an urban police department claims that the proportion of crimes committed after dusk will fall below the current level of 0.84 if led streetlights are installed. specify the null and alternative hypotheses to test the police department's claim.

The required null and alternative hypotheses are and respectively.

Step-by-step explanation:

Consider the provided information.

If there is no statistical significance in the test then it is know as the null which is denoted by , otherwise it is known as alternative hypothesis which denoted by .

The claim is: The proportion of crimes committed after dusk will fall below the current level of 0.84

The null hypothesis is The proportion of crimes committed after dusk will same as the current level of 0.84.

Therefore,

Hence, the required null and alternative hypotheses are and respectively.

c

step-by-step explanation:

if gloria has "carry over" minutes, (that is, any minutes paid for but not used in a month can be applied to her payment for minutes in the next month,) her total usage for the three months is: total minutes = 320 + 243 + 489 = 1052 minutes number of 200 minute blocks = 1052/200 = 5 r52 (that is 5 with a remainder of 52) rounding up the number of 200 minute blocks gives her usage for the three months as 6 blocks. the cost for six blocks is 6 x $25 = $150 she also has 200 - 52 or 148 carry over minutes if gloria pays each month and unused minutes are lost, applying the rounding up procedure to each month gives: first month usage of 320 minutes rounds up to 2 blocks of 200 minutes for a payment of 2 x $25 = $50 second month usage of 243 minutes rounds up to 2 blocks of 200 minutes for a payment of 2 x $25 = $50 third month usage of 489 minutes rounds up to 3 blocks of 200 minutes for a payment of 3 x $25 = $75 total payments for the three months are $50 + $50 + $75 = $175 get the plan with carry over minutes!