Answer:
1.-Then we p-value indicates that we are in the rejection region we reject H₀ 
We support the claim of the garbage collector the average picking up more than 4 tn of garbage
2.- p  = 75 %
3.-3.-t(s) is in the rejection region we accept H₀ we have not evidence to support Marc´s claim
Step-by-step explanation:
1.- If p-value is 0,04   and significance level α = 5 %  or  α = 0,05 then p-value < α 
Test hypothesis should be    ( x the average of garbage)      
Null hypothesis          H₀           x = 4 Tn
Alternative Hypothesis     Hₐ    x  > 4 Tn
Then  alternative hypothesis suggests a one tail-test to the right  and
p-value <  0,05
Then we p-value indicates that we are in the rejection region we reject H₀ 
We support the claim of the garbage collector the average picking up more than 4 tn of garbage
2.- As we are dealing with a normal distribution the CI  95 % is symmetrical with respect to the mean, therefore the proportion of student living in Brooklyn is:  
(0,73 + 0,77) /2
p = 0,75     p  = 75 %
Test hypothesis:
Null Hypothesis            H₀            μ    =  26
Alternative Hypothesis      Hₐ      μ   <  26
Alternative hypothesis tells us the test is a one-tail test to the left
Sample size   n = 25
Sample mean   μ  =  24,4
Sample Standard deviation  =  9,2
We assume normal distribution, and as n < 30 we use t-student table
with  24 degree of freedom
Significance level is 0,05  and df = 24  we find t (c)  in t- student table
t(c) = 1,7109      test to the left   t(c) = -1,7109
To calculate  t(s)
t(s)  =  (  24,4 - 26 ) / 9,2 / √25
t(s) =  - 1,6 * 5 / 9,2
t(s) = - 0,87
Comparing t(s)  and t(c) we have
t(s) > t(c)
t(s) is in the rejection region we accept H₀ we have not evidence to support Marc´s claim