Need help these two questions

18. Soccer is also called association football." A soccer ball is a sphere, with a circumference of 70 centimeters [cm]. In developing a new material to use for a soccer ball when NASA attempts to colonize Mars, you test a material with a specific gravity of 1.21. Assume the ball will be a solid sphere made from this material. What is the weight in units of newtons [N] of the ball on Mars? Recall gravity on Mars is 3.7 meters per second squared [m/s] Recall the circumference of a circle is equal to the diameter times pi: C = D 7. The European Space Agency launched a probe called Rosetta in March 2004. In August 2014 Rosetta reached its destination: a comet called 67P/Churyumov-Gerasimenko. Rosetta is the first spacecraft to rendezvous with a comet It contained a lander craft, called Philac The Rosetta has a launch mass on Earth of 3000 kilograms [kg] and the Philae has a launch mass of 220 pound-mass [lb ]. In order to escape Earth's gravity, the combined space craft [mi/h How much thrust, in t must accelerate at a rate of 25,000 miles per hour squared units of newtons [NJ. must the engines provide to reach this acceleration