Measurement - Tank problem

The Port of Tauranga Company has allowed Gull to build a new cylindrical petrol storage tank at Mount Maunganui.

To help plan for this tank, complete the following calculations (show all working)

1a-(L3) The tank will site on a rectangular site 70 m long by 50 m wide. This needs to be laid with cobblestones. Work out the area in m2 

1b-(L4) Work out the area in hectares.

1c-(L3) Wooden boxing will need to be placed around the outside of this rectangle. What is the total length of wood needed?

2a-(L3) The tank has a diameter of 40 m. What is the radius?

2b-(L4) What area will the base of the tank cover?

3a-(L5) The concrete foundations need to be 75 cm thick. What volume of concrete will be needed for the base? (assume the foundations will be circular)

3b-(L5) The capacity of a concrete truck is 5 cubic metres. How many trucks will be required to pour the base?

3c - (L6) Steel reinforcing needs to be used for the foundation. A total length of 250 m will be used. The steel reinforcing is a solid cylindrical rod,  1.5 cm in diameter. What will be the new volume of concrete required taken into account the volume of the steel reinforcing?

3d - (L6) Cost for concrete delivery is $170 per truck plus $50 per cubic metre of concrete. What will the total cost of the concrete be?

4a - (L5) Once completed, the tank will hold 2, 000, 000 litres. How many cubic metres does this equal?

4b - (L6) How tall must the tank be?

4c - (L6) If two thirds full with fuel, how long will it take to pump in the remaining third if a tanker can pump 17 cubic metres of fuel per hour?