An observer sees two spaceships flying apart with speed 0.99c. what is the speed of one spaceship as viewed by the other?

The us government wants to allocate billions of dollars in the next 10 years to assure our future energy security. the funds will be spread among a variety of possible energy resources. where do you think the government should put the greatest support: solar energy, wind energy, clean coal, oil exploration, gas exploration, or a combination of sources? are there other efforts that should be explored? support your position with cited information for both questions.

How many seconds does it take a pebble released from rest off a bridge to fall 29.4 m ? what is the pebble's speed when it has fallen 29.4 m ?

Which transition by an electron will release the greatest amount of energy? oa ob oc od