A cell phone store sells the basic model of a phone for $30 and the upgraded model for $100 when a customer signs a two-year agreement. On Tuesday, the store has $900 in sales. The store pays $5 for each basic model and $25 for each upgraded model. If the cost of the cell ...
June 17, 2014
The Earths radius is about 6380 km. The space shuttle is orbiting about 300.1 km above Earths surface. If the average speed of the space shuttle is 25700 km/h, ﬁnd the time required for it to circle Earth. Answer in units of h
September 28, 2011