A set of plans shows that an opening in a bulkhead is needed for a section of pipe to pass through. The plans show metric values, but the only tape measure available is marked in inches. The pipe is shown as a size DN80 (a European pipe-sizing standard), and a chart indicates the outside diameter of DN80 pipe is 88 millimeters (mm). According to the plans, all openings must be 40 mm larger than the pipe. You know that 25.4 mm is equal to one inch. What is the diameter of the needed opening in inches? Round your answer to the nearest whole inch.

Aspacecraft can attain a stable orbit 300 kilometers above earth if it reaches a velocity of 7.7 kilometers per second. the formula for a rocket's maximum velocity v in kilometers per second is vequalsminus0.0098tplusc ln upper r, where t is the firing time in seconds, c is the velocity of the exhaust in kilometers per second, and r is the ratio of the mass of the rocket filled with fuel to the mass of the rocket without fuel. find the velocity of a spacecraft whose booster rocket has a mass ratio of 20, an exhaust velocity of 2.1 km/s, and a firing time of 15 s. can the spacecraft achieve a stable orbit 300 km above earth?