1. Realize that both passenger cars and trucks are part of private vehicles. Hence instead of calculating percentage of each and referring to the graph for the number of private vehicles and then cancelling at the end, simply making the ratio of given % of each will lead to faster result. $\frac{4}{60}$ ($59.5$ is approx $60$)= $\frac{1}{15}$

2.In the bar graph approximately $120000$public vehicles were there in 2005. Checking the pie chart for public vehicles only Misc is $4% of 120000 = 4800$ and trolley bus is $1.5% of 120000 = 1800$
Hence $4800 - 1800 = 3000$

3. Given, $1995 = 572000; 2005 = 785000$
Hence % increase = $\frac{785000 - 572000}{572000} * 100 = 37.23%$ approx $37%$

4. This is slightly tough as both pie charts and the bar graph has to be referred for answers.
First of all find out the total number of passenger cars = $60% of 225000 = 135000$ [Here $225000$ is approximately the number of total private vehicles]
Now Find the ratio of malfunctioning cars to total = $\frac{13436}{135000} = 0.099$ approximately =$0.10$

Now refer the bar graph again and the total number of public vehicle is approximately $120000$
Demand response vehicle from the pie chart is $24.4% of 120000 = 29280$ now if $0.10$ of these vehicles had mechanical failure than the total number of such vehicle would be
$29280*0.10 = 2928$